For such widespread adoption, that people have to continue to use it, no matter what the option is. Pay sites grow slower than free sites. Twitter has money in the bank, so it can afford to stay free for a while, thus growing. So when it's big already, it starts monetizing. If it starts monetizing too early, growth will slow.
That's a ridiculous notion, though. If not paying for the service still allows you to do everything twitter provides save for a small subset of features, it doesn't prevent folks from joining and seeing the value of it.
Being afraid to generate revenue before hitting critical mass sets this silly precedent that you can't flip the switch until you reach a mythical number of users.
I'm not saying Twitter couldn't make a bunch of money, but for every YouTube and Twitter waiting to hit it big, there are 1000's of companies thinking this is a viable solution to their problems and failing because of it.
So the negative effect of Twitter not having a publicly announced business is felt primarily by other companies, companies that aren't able to think for themselves?
I'm not sure I buy that. There are plenty of companies, like your own, that understand what their business needs. And there are always going to be plenty of other companies that behave like sheep. If it wasn't Twitter, they'd find some other trend to misapply.
Paying big time, too. And not just for premium memberships that allowed more InMail -- IIRC their recruiter-tailored service runs at $25K a year. I pitched hard for it when I was a recruiter, but we were stuck in the cold-calling age. I lasted about another 2 months.
The idea that they want to keep growing as fast as possible, and they don't want to retard growth by monetizing makes a lot of sense to me. It especially makes sense because people are using the product in ways that the Twitter guys never even imagined. They don't even have to figure out new ways to use Twitter, their users are doing the creative stuff for them, they just have to pay attention. But if you monetize in the wrong way, it can have the unintended consequence of preventing some awesome-currently-unimagined use of Twitter. And that is much worse than a change to an abstract growth curve.
The other thing I wonder about is if their monetization strategy involves some technical challenge. Remember, their product is relatively straightforward from a technical standpoint, not to trivialize what they've done at all, just to make the point that they have gotten here in a short period of time with a very small number of guys. What if their preferred method of monetization involves solving some technical problem that they just haven't resolved yet?
When was the last time you saw twitter down? Last time I remember seeing the fail whale is probably back in October or earlier. They did have major uptime issues but I think that's mostly in the past. I'm not on 100% of the time so it's quite possible I missed a few sightings but back in the summer and fall it would go down a lot whereas now it's a rare occurrence.