I buy games to play, but because I have so many and becauase I buy games often enough, around 5% or 10% of them remain unplayed for months, 2 or 3 will remain unplayed for more than a year, since I can't play everything at once. If there's a game that I don't like and I know I'll never be interested in playing again, I'll just sell it for whatever money I can get for it, and if I can't sell it, then I'd happily give it away.
This is why I have an end goal, a cut off point, where once I've got all of the games I'm interested in playing for the 4 systems I own, that'll be it, I wont be buying any more. Because as well as not wanting to have too many games, I want to play all of the games thoroughly that I enjoy in my life time.