The best part for me is they get you to play a game inside out, it sort of makes me feel like a kid again.
As a kid I had no choice but to master games and do EVERYTHING as I wouldn't get another for a good few months. I'd explore all corners, do all difficulties etc. Anywho, then I grew up, got a job, and wouldn't really give the games the playthrough they deserve.
Trophies give me an incentive to not skip the hardest mode or miss the secret area just cause something else is out, and you get a sense of achievement out of it more then just doing it in the first place. Obviously I'm not going to bother if the games sucks or the trophies are boring, but alot of the time they just extend a games life and allow me to give it the attention it deserves.
They made me enjoy games alot more again for some reason... probably because it's lead to me playing them more and waiting for new releases to get cheap :).







