I've noticed that when I'm working on personal projects or (to a lesser extent) complex games, my motivation to continue working or playing drops off significantly as soon as I've figured out the solution for the project or the optimal strategies for the games. The sensation is a bit like, say, playing an RPG and doing some postgame quest for the Infinity+1 sword, and then not wanting to play anymore once you have it -- I worked hard to get a godweapon but don't have any urge to use it. This is particularly frustrating for programming projects, that tend to get dropped unfinished after the major problems have been solved.

I don't really have any point to make with that. It's just irritating.