https://en.m.wikipedia.org/wiki/Principal%E2%80%93agent_prob...
The shareholders are uninformed and disorganized. They might take their money out but that will take a long time. Meanwhile, management and the board control the flow of information and can take decisions together.
The theory is wrong, basically, if that's what it says.
Granted bad deals get made from time to time.
I've seen way too many PMs and middle managers twiddling their thumbs and just inventing tasks and reports just so they are busy and are not fired.
How do I know? We had some of them go to a conference once; they were all gone for two weeks.
Work was going faster and smoother.
And that's not a single anecdote, it's supported by many other programmers.
Truth is, nepotism and "we've been buddies at the uni" is happening much more than you are willing to admit.
> Just because you don’t see the value doesn’t mean there is none.
Sometimes it is absolutely true, which is most often seen in nepotism but also in categorically stupid people (re: Bonhoeffer).
That's like asking the corrupt politicians to uproot corruption. Obviously it will never work.
So the shareholders get bulshitted exactly by the people who are very likely superfluous.
Besides, information is so wildly far from perfect in all spheres that we rarely see anything particularly close to the extremes of efficient behavior predicted by spherical-cow market fairy tales anyway, even when market forces are fully in-play.
See: AT&T