I haven't left, but I almost have on a few occasions (18 years in starting at a call center, then to desktop/client support, then sysadmin, then web developer,

I haven't left, but I almost have on a few occasions (18 years in starting at a call center, then to desktop/client support, then sysadmin, then web developer, then system engineer, now dev lead that does a lot of architecture work). When I almost quit: Incompetent leadership: bosses and leaders that are seemingly nice people, but have no clue as to what's going on in their organization. Typically managers that aren't technical at all, but they just "fell up" in the organization somehow. Relatively low pay: speaks for itself. It's easier to deal with hard problems and difficult people when you're also not worrying about which bills to pay this month, and seeing your peers in other companies do a lot better than you. This was especially true when I was in academia. Toxic work environment: This unfortunately has happened a couple of times, once in a small family-run shop (13 people) and once in academia (a different role than the aforementioned one). There was a common denominator with both - the person at or near the top was a nasty combination of incompetent, bitter, and pit their employees against each other. In other words people that were truly pathological. All in all in my career I've reported up through dozens if not over a hundred people total through the various chains of command, but these two stand out. With one in particular there's a bit of PTSD (in the small shop the CEO would threaten jobs for minor things - this was ~2010 when the economy was still near the bottom where I live, and his COO would do equally vicious things). I work for a great company now with some of the most awesome leadership you could ask for. I'm glad I didn't quit.