I'm not doubting your reasons at all; I have many myself. What dissapoints me most is that it would usually be so easy to do better, get better results, leave everyone happier.

Think also of all the reasons you have to believe; we see what we look for. People will let me down sometimes and will lift me up others. Neither solution, cynicism or optimism, gets perfect results or guarantees success or happiness. The latter sure feels better, especially if you accept that it won't always work, and most of all I think: Which sort of person do I want to be; where do I want to lead people? And finally, I find that people follow where you lead and act how you treat them, to a shocking degree; IMHO they follow the norm that they perceive; I try to set a positive norm and people surprise me often.