To an optimistic perfectionist, the initial outlook is always rosy; but the reality is always more complex than expected, and the work always takes longer than anticipated.
(Managers have a love/hate relationship with us. They love the final results, but they hate the fact that they have to double our initial estimates, add contingency, double them again, and finally add a fudge factor to compensate.)
See also: xkcd: Success
I know what you mean about managers love/hate relationship. I have to manage an optimistic perfectionist and it’s crazy. It’s myself and I’m very hard to manage!