Honestly, I think that VC-istan companies do a horrible job of instilling loyalty. Equity percentages are low enough that I'd rather take a full salary. True business partnership is worth going down in salary to "buy in", but if you don't get to know the cap table or at least know that there isn't some VP of NTWTFK (Non-Technical Who The Fuck Knows) getting 20x as much, then what's the point? You're getting paid in lottery tickets, you can be cliffed, the offer may be rescinded if you start asking about liquidation preferences, etc.
Also, these companies generally have tight deadlines (because they grew too fast and blew up their burn rate) and can never invest any time in doing things right, much less employee mentoring. With no loyalty to employees, these startups get none back.
Finally, when you're forced to implement bad practices (technical debt plus unhealthy work conditions) to meet these deadlines, you want to run as soon as you hit a macroscopic target, in order to (a) cash in while there's a glow on your face, making that social bump permanent, and (b) avoid suffering or being embarrassed when things start to fall to pieces.
Also, these companies generally have tight deadlines (because they grew too fast and blew up their burn rate) and can never invest any time in doing things right, much less employee mentoring. With no loyalty to employees, these startups get none back.
Finally, when you're forced to implement bad practices (technical debt plus unhealthy work conditions) to meet these deadlines, you want to run as soon as you hit a macroscopic target, in order to (a) cash in while there's a glow on your face, making that social bump permanent, and (b) avoid suffering or being embarrassed when things start to fall to pieces.