"Don't procrastinate, communicate clearly" are to management what "eat less, exercise" is to losing weight or "only buy things you need, spend less than you earn" is to saving money.
The problem isn't managers that they haven't read this compilation of checklists or its equivalent in any of the thousands of management books out there.
The problem is the brokenness of management as a role in general.
Too many organizations are stuck in an broken structure which makes management the most direct if not only way to advance in terms of status, pay, autonomy or all three.
The end result are incompetent managers who need to be taught common sense or unhappy ones who are far better suited to other roles, but recognize them as dead-ends.
If becoming a manager stops being desirable for all the wrong reasons you won't have to remind your new, inexperienced managers not to be lazy or not to manage by intimidation.
I agree, and would add that they're not even answering the specific question being asked (which happens a lot on Quora). The question they're all answering is:
"What is good general management advice?"
But the question that was asked is:
"What are mistakes specific to new, inexperienced managers, that are common for that particular class of managers?"
A responsive answer to that question will generally be expressible as,
"The manager will make it a policy/habit that <blank>, thinking that <poor recognition of group dynamics>. In reality, <mechanism happens> and so they encounter <failure mode>."
"The manager will start a policy of not tracking employee time, on the grounds that the group is responsible and trustworthy, not realizing that this will make it harder to demonstrate progress and efficiency to higher-ups, and result in less leeway being given to the group on important decisions."
[Please don't refute the logic there, I'm not offering it as valid, just showing the form that a responsive answer would have.]
Also - do you think it's that their overwhelmed, under-trained for the new demands of the role, or something else that causes so many managers to fail?
I think that making available a number of paths for growth is certainly a good thing. I expect there are size limits on such a structure - either for the company as a whole or the extent of the company that gets to experience that track.
This is something I'm very curious about - small companies which have managed to keep their employs happy, well-paid and continuously growing (as individuals).
>'Also - do you think it's that their overwhelmed, under-trained for the new demands of the role, or something else that causes so many managers to fail?'
I doubt there's ever truly a single source for manager failure, but if I had to bet on the most significant variables in failing in a typical situation I'd say:
* Promotion Beyond Competence:
Happens for all sorts of reasons - nepotism, stereotyping, political maneuvering (puppet appointments), adherence to tradition and many more.
However it happens, the person is not properly equipped for the role, in the worst case it's to such a degree that they don't recognize how far they fall short.
* Lack of Ambition / Urgency:
If it ain't broke, don't fix it. If it is broke, don't fix it. There's too much risk. No reason to rock the boat and jeopardize a steady, comfortable paycheck.
* Unmanageable People:
I expect lots of people have never worked for a good manager of any measure. That bad experience makes them utterly certain that anyone who isn't 'in the trenches' 100% of the time useless - a drain on their productivity.
So, once the good one comes along - the one who will make him/herself an impenetrable human bullshit shield for 98.6% of every day in exchange for a 5 minute status report - they refuse to offer up that barest minimum.
EDIT: There's also the corresponding "Dilbert Principle"  which states that incompetent employees are promoted intentionally to remove them from the productive flow.