I have mixed feelings on the subject. In one respect achievements/trophies add replay value to games that might just be considered throwaways once you finish the main campaign/story. On the other hand, just playing a game to experience and enjoy the game without worrying if I'll be able to 100% the game was a very liberating experience (when I got back into Nintendo gaming). Having the merits of a game determine if you wanted to play it more rather than worrying about an imperfect score was refreshing.