
Preventing users from pouring water into coffee machine beans compartment - laurent123456
http://ux.stackexchange.com/q/34126/7235
======
veemjeem
This may sound dumb, but maybe the easiest solution is to put a transparent
fake water container that never drains. So anyone who is about to pour water
would see that the machine already has water.

Since the machine in question is hooked up directly to the tap, one never
needs to fill it with water.

~~~
daemin
That's what I was thinking, but then the water would stagnate, go green, and
be a potential source of mosquitos. So someone will want to change it.

The fix would obviously be to make a little bit of the water be drained away
whenever a coffee was made, but then it would need refilling and you're back
to a situation where you might as well just have 2 containers and disconnected
from the water supply.

~~~
bathat
Since the false water container on top isn't going to be used anyway, what
about just filling it with something hostile to microbes, like dilute hydrogen
peroxide? If you wanted to get really fancy, you could even add a couple lines
marked "max" and "min" and add some plumbing to make the fluid level vary
between them.

~~~
daemin
Apart from the problem of having potentially toxic substances as part of a
beverage generation device, adding extra moving parts to simulate a non-moving
part is really adding unnecessary complexity, effectively trying to fight
against the universe (and the idiots that it produces).

------
daemin
This brings up a sad story from my old work.

We had a coffee machine where you had 2 containers, one for the beans and one
for the water, never had a problem with knowing which was which. But there was
also a place to put in pre-ground coffee, which we never used.

One day a consultant came along, and not being able to make coffee because the
machine had run out of beans, they proceeded to pour beans into the space
reserved for the pre-ground coffee. We found this out by the horrific gear
crunching noise the machine had made as the coffee beans shredded the
internals to bits. It was a disappointing and sad day for the engineers, many
of whom were frequent coffee drinkers.

Needless to say after the machine was repaired we taped that pre-ground coffee
access port closed.

~~~
tzury
That's a nice story of how a consultant have ruined the engineer's day.

~~~
jarek
You could also say it's a nice story of how a lack of documentation caused
pain for both consultant and engineers.

~~~
RyanMcGreal
And yet the premise of good UI design is that it should be self-documenting.

------
jmvoodoo
I was going to post something on their site, but apparently you have to have
enough karma to give a response now.

Use a removable side-loading bean cartridge. The bottom of the cartridge would
be mesh, the top open. There would be a spring-loaded door on the side of the
cartridge that the machine would open once inserted (or it could be opened via
a "lock" lever for a pure mechanical solution) so that beans could flow out.
This way it could never be loaded with water, and the beans would stay fresh
since once inserted the cartridge would be sealed on top and bottom by the
rest of the machine.

~~~
csense
I actually somehow haven't jumped on the StackOverflow bandwagon yet. If you
need karma to reply to questions, how do new users get karma?

~~~
kpreid
Only specific questions:

“This question is protected to prevent "thanks!", "me too!", or spam answers
by new users. To answer it, you must have earned at least 10 reputation on
this site.”

It's basically like semi-protection on Wikipedia: things which have gotten a
lot of attention can get lots of noise, so only more established users are
allowed to add content.

------
edouard1234567
All you need is to design your bean enclosure so it's never completely empty.
The few beans trapped in what I'd call a "reminder reservoir" will be enough
to remind users beans go here.

~~~
rcsorensen
If you can do this and keep the beans segregated, this is far and away the
best solution.

Even just gluing a coffee bean or two to the outside might work.

------
just_observing
"a brief hand-crafted manual"

You deserve your problem if you use that terminology for whatever people are
not reading.

------
mhb
Eliminate the bean compartment and dispense the beans from a centralized
location just like the water. Either using an augur or a pneumatic tube
delivery system.

~~~
pavel_lishin
The best part about this solution is the inevitable conspiracy theories about
the Government fluoridating our beans.

~~~
sdoering
Thanks a lot, as it is early in the morning here, you just made my day start
better with a little laughter.

------
stephen_g
The coffee snob in me wants to say that for a nasty automatic machine like
that, putting water in the bean hopper and breaking it is probably a good
thing! Seriously, used commercial machines are fairly cheap and will make a
far superior coffee which is worth twenty seconds of work.

But if you must, I like the idea of a bean container that must be removed to
be filled. Better than warning labels (that people will ignore) or putting a
picture of a bean there or something.

~~~
hartror
We have a proper machine in the office and some people still drink _ugh_
instant. At least with a machine like we are discussing people will drink a
better standard of coffee than they otherwise would.

~~~
ahoge
>some people still drink [...] instant

They probably just don't know how to operate the machine.

~~~
jaredmcateer
I actually know people that prefer the taste of instant. I think it's one of
those things where if you're raised on garbage, you'll like the taste. I know
for a long time I though Tim Hortons coffee was the tits.

------
dsr_
The coffee machine I have in my house does not have this problem. It is a very
common machine, and there are many like it.

Here's one much like it: <http://www.mrcoffee.com/Product.aspx?pid=7645>

You take the carafe out. You fill it full of water. You open up the top of the
coffee machine, and you have a choice:

You can pour water into the reservoir, or you can pour it through the filter
basket and thus on to THE FLOOR because the carafe is in your hand.

People learn quickly how to use it.

Here's a commercial one with a similar lack of problems:
[http://www.amazon.com/33200-0015-VPR-2GD-Pourover-
Commercial...](http://www.amazon.com/33200-0015-VPR-2GD-Pourover-Commercial-
Decanters/dp/B0037XIP22)

The water goes in the top. In order to load ground beans you have to pull out
the filter basket. No confusion possible. Trying to pour water into the filter
basket results in water on the floor. Instant feedback.

~~~
veemjeem
You're just linking to an average drip machine, which obviously doesn't have
these problems, but it doesn't help the stackoverflow user who had the
original question. The machines he was asking about have a separate container
that stores beans that are automatically ground. These are fully automatic
machines where you push a button and coffee comes out, no interaction is
needed by the user, and yet the user will sometimes "think" action is required
and will mistakenly fill the bean storage with water.

Your "commercial" drip machine is probably only a few hundred dollars at most,
but the fully automatic machines are in the thousands of dollars, so repair is
pretty expensive.

------
silasb
Why not actually fix the problem.

If people put water into the bean compartment then don't kill the machine. How
you ask:

Water bypass valve used in Cold Air Intakes to prevent your engine from
drinking water.

[https://www.google.com/search?q=cold+air+intake&hl=en...](https://www.google.com/search?q=cold+air+intake&hl=en&tbo=d&source=lnms&tbm=isch&sa=X&ei=jHASUZbeIu-r0AH9wYCICw&ved=0CAcQ_AUoAA&biw=1284&bih=963#hl=en&tbo=d&tbm=isch&sa=1&q=cold+air+intake+water+bypass&oq=cold+air+intake+water+bypass&gs_l=img.3..0i24.1765.3328.8.3451.8.0.8.0.5.0.0.0..0.0...0.0...1c.1.2.img.uCfNDZ3ng_o&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&bvm=bv.41934586,d.dmQ&fp=83efe7823b09c1df&biw=1284&bih=963)

------
biot
Have a fine mesh on a 45 degree angle that will allow the whole beans to slide
down the mesh, but that water will pass straight through. The beans slide into
a permanently covered bean receptacle that is impossible to add water to
without disassembly (which should be an option for cleaning).

Beneath the mesh you could have a catchment to collect small bean particles
and any water that the user tries to add, and the design and placement should
be quite obvious that water poured onto the mesh isn't going anywhere.
Conversely, let it collect there and go nowhere. If that catchment overflows,
it goes onto the counter.

~~~
kordless
I worked at a place where someone (who we never caught) put some chocolate
coffee-bean-look-alike candy from Trader Joes in the grinder. All the new
peeps (myself included) got 'blamed' for being ignorant, and lots of signs
went up. I hate signs because the can never anticipate all scenarios.

My next work place had someone try to cook bacon in the toaster oven. As it
turns out, this is not a viable way of frying bacon and it caught the toaster
and part of a cabinet on fire. Later that month the building management
started doing regular fire drills. We'd take the opportunity to tell the story
about Mike and his bacon as we stood on the street.

I'd say people were idiots, but that's a negative view practiced ineffectively
by the first place. I'd rather see it more like people incorrectly assume what
they are doing is right, and never question if its not. Silly humans.

~~~
fusiongyro
Signs are also stupid because they're built on two faulty assumptions: one,
that the morons read them, and two, that the mistakes of the future will be
carbon copies of mistakes of the past. There's no bacon frying sign over the
toaster oven at my work, and I've seen people cook bacon in the kitchen. But
there's a sign over the sink listing things that shouldn't go down it, as if
nobody has one of these things at home.

------
monksy
Wouldn't a label for this suffice? Who's going to read a manual only to find
out that this is connected to the internal plumbing?

~~~
hcarvalhoalves
If it's obvious enough, it won't need labels. In fact, the right way to design
these kind of products is to assume the person using it cannot read.

~~~
daigoba66
Perhaps a label and a "no water" symbol? Like this:
[http://thumb15.shutterstock.com/thumb_small/290671/290671,12...](http://thumb15.shutterstock.com/thumb_small/290671/290671,1263638117,28/stock-
vector-vector-illustration-of-modern-icon-depicting-a-not-pouring-liquid-
signal-44588677.jpg)

~~~
monksy
That sounds like madness.. The doors that way!

------
vacri
Use a padlock. Put the key where only knowledgable users can find it. This
will cut down on your casual visitor screwing things up.

Engineer a dyson-vacuum-cleaner-like apparatus which 'sucks' water and beans
in different ways.

Do the first comment's ideas, but make it a two-stage event - first is to put
the item on the grid/flap, second is to manually fold the gridflap into the
machine, where it's dumped into a temporarily unsealed beanbox. Water won't
stay in the grid long enough to hang around for the second stage.

Create a sniffer that requires the scent of a fresh bean to be presented
before opening the port.

Drink hot chocolate instead

Sell special iron-laced beans and use a magnetic apparatus.

~~~
Matti
A label saying "This container is for coffee _ _ _ _ s" with a lettered
padlock (<http://wordlock.com/padlocks/>) would perhaps be preferable to the
hidden key solution.

------
stephengillie
I'm going to bring up the Microsoft Starbucks machine again, as it has also
solved this problem. They used the 2nd solution - a water line directly to the
machine. Also, the beans-hopper holds 2 kinds of beans, usually house blend
and decaf, which rarely go empty at the same time.

No worries about watering the hot chocolate powder hopper, either. says "Hot
Chocolate" on the compartment lid, and inside it's covered in chocolate dust.

~~~
aptwebapps
Read a little more closely: the machine in question has a direct water line
but people still occasionally put water in the bean compartment.

My theory: <http://news.ycombinator.com/item?id=5175098>

~~~
stephengillie
I'm not sure if you've seen one of these coffee machines. When you come to
one, your first thought isn't "where do I put water", it's "what kind of
coffee do I want?"

Here it is, to the right of a Keurig coffee pot:
[http://static3.businessinsider.com/image/4ef3bec5ecad04cd2c0...](http://static3.businessinsider.com/image/4ef3bec5ecad04cd2c00002d-900/the-
company-used-to-have-a-keurig-coffee-machine-but-it-got-a-starbucks-coffee-
maker-for-this-new-space-people-are-very-happy-about-it.jpg)

~~~
aptwebapps
The article already has a picture and it is a bit different than that.

Even with machines where you have to put the water in you don't have to do it
for every cup, most likely people either put water when they put in beans,
because that's what they are used to, or perhaps when the machine isn't
working properly and they are trying to get it going again.

------
nisse72
We have a cafe style coffee grinder (next to our manual espresso machine) that
has two hoppers: one for the beans, and one where the ground beans end up,
from which you dispense into the porta filter.

I am guilty of filling the wrong hopper with beans (talking instead of paying
attention). Twice. Not quite as bad as water, but still a PITA to pour
everything out and separate the beans from the ground coffee.

------
beedogs
hire smarter people? I've never heard of this happening; I didn't know people
could be that dimwitted.

~~~
guizzy
You've got to remember: we're talking about people who haven't had their
coffee yet.

~~~
mkopinsky
Not long ago I discovered that the coffee machine works better when you put
the cup in place BEFORE pushing start.

------
moe
How about a visible warning sticker "Don't pour water here" (ideally with a
pictogram for people who can't read)?

------
snarfy
"Programming today is a race between software engineers striving to build
bigger and better idiot- proof programs, and the Universe trying to produce
bigger and better idiots. So far, the Universe is winning."

The machine is fine. Your users are broken. Make the person that destroyed the
machine pay for it.

------
obeattie
I don't know what goes on inside the coffee bean hopper, but fundamentally I
can't see why one couldn't just prevent the machine from breaking if the user
does make a mistake. The machine could then warn the user of their error and
allow them to correct it. They'd soon get the idea.

------
smosher
Load the beans from underneath using a detachable tray with a mesh inlay which
will is used to pull the beans in.

(If you must go all out, put a bob that opens a trap in the bottom of the tray
so they can't get the water near the machine if they try to fill the tray with
it.)

------
hermannj314
This is full of very serious answers. I thought this was a rhetorical question
to highlight the tendency of software developers to mismanage risk.

I feel like no matter what the answer is, the questioner could just throw
another "But what if..." on top of it.

 _Set a post-it note saying "Water here"._ But what if a Black Hat gains
access to the coffee machine and moves the sign? Etc. You can't win unless you
know what the questioner wanted to hear. I guess that makes it a good
interview question.

~~~
iaskwhy
Adding to that, regarding a comment on that thread: "It'll probably still be
gotten wrong by the same people who push on 'pull' doors". Culture is very
important. In my native language, 'push' actually means pull! I will always
get that wrong unless the design is good, meaning there's only one handle and
it's on the side you actually need to pull. If there's an handle and the word
'push' just by its side than I'm going to pull it no matter what.

~~~
limmeau
What language is that?

I usually fail at glass doors when PUSH and PULL labels are transparent so
that I read "PUSH" and (reverse) "PULL" simultaneously.

~~~
andos
Portuguese, "puxe": <http://translate.google.com/#pt/en/puxe>

X sounds like SH.

------
drewwwwww
a coffee machine like this is guaranteed to make terrible coffee. the solution
is to have better equipment.

if you see a coffee machine that has bean storage, it's almost guaranteed to
suck.

------
decklin
Don't put the coffee machine next to the sink or water cooler.

~~~
VLM
Simple elegant and effective. If it takes one second to transfer water from
sink to machine, you only get one second to process the data and possibly get
the wrong conclusion. If it takes 60 seconds to walk across the room, that
provides time to think ... why did they make it so hard to add water to this
thing? Plenty of time for data processing to kick in and notice ur doin it
wrong

------
perlgeek
I'd put a transparent foil on the beans container that shows, well, coffee
beans. That way it should be obvious what it's used for, even if it's empty.

------
d33pika
Don't have any opening to fill in beans or by mistake water, Get beans in a
sealed container, sealed with cardboard at the bottom, which the machine can
penetrate. Another solution is to connect bean jar through a pipe to bigger
source of beans similar to how water is sourced. The bean source is maintained
by a dedicated person. If they cannot learn how at use it,restrict access
thats the way to go!

------
TelmoMenezes
Make holes in the beans compartment that are too small for the beans. That
would make it very obvious that pouring water there is pointless.

------
oelmekki
I have a saeco odea, they designed the bean recipient so it looks more like a
curved plate than a bottle : <http://imgur.com/CJzJLQ3> .

I think it's quite obvious to the user you don't put water in this.

On the other side, the water tank is a bit hidden, being inside the machine,
behind an opaque face. Making it transparent would probably help.

------
aptwebapps
I can easily envisage some people putting water in the bean hopper simply
because they couldn't find anywhere else to put it.

------
D_Alex
So... Where I used to work, someone once put milk in the water container, 'cos
they thought that's how you get frothed milk.

------
8ig8
What about making the coffee receptacle resilient to water?

Let the water filter through the bean mechanism without damage. Catch the
water in that bin under the cup.

Worse case you overflow the bin, but you learned a lesson and didn't break the
coffee maker.

------
noknockers
Which company would ever stop this from happening? More breakages = more
money.

------
vaidhy
Make the hopper transparent and stick the picture of beans to it so that it
looks like it is filled with beans. It makes it obvious and gives an immediate
adverse reaction to someone trying to pour water.

------
gcb0
As someone who actually has a major in product design, that link and this
thread is pure gold!

I'm getting the same dark satisfaction as if I were reading how to write your
own encryption algo at phpscripts.com

...time to make some popcorn.

------
malkia
Surely this needs needs Mr. Bean pointing finger.

------
niccl
For lots of stuff along these lines, Donald Norman's Design of Everyday Things
is highly recommended.

------
taylorwc
Try a passive aggressive note yet? Humiliation is a fantastic break room
tactic.

~~~
_pmf_
I don't subtlety works on the target demographics.

------
dear
Just give everyone a training course for using the machine.

------
stevvooe
French press, anyone?

~~~
alistairSH
Keurig machine in the kitchen here. I'm sure it offends the coffee-snobs, but
it works for me (I drink tea, not coffee, so just use it for hot water).

~~~
stevvooe
No offense taken ;).

It's just that there is a lot of thought wasted solving a derivative problem
that could be avoided by continuing to use a simpler solution to the first
order problem. This is classical overengineering. At the same time, any good
solution to the coffee problem will likely have to find a tuned balance
between a number of traits and they will be different for each person.

There are certain abstract tradeoffs that aren't taken into account in the OP
(if I remember correctly). In the case of the keurig machine, it solves the
complexity and convenience by narrowing flexibility, increasing expense and
maybe sacrificing taste (which are all completely valid tradeoffs). The french
press or a ceramic dripper maintain the flexibility, expense, taste and
minimize complexity at the cost of convenience.

------
CyberDroiD
I don't understand this: "Typical coffee machines have two user-accessible
compartments - one for water and one for coffee beans".

No they do not. Most "Typical coffee machines" require ground beans in a
basket. The coffee maker described as typical is actually something I have
never seen before.

Try a Kuerig if you want a cool coffee maker! But they again are not "typical
coffee machines".

