Copyright (and all intellectual property in general) should have a "use it or lose it" provision, just like trademarks. If there's a piece of software that you own but aren't interested in selling or maintaining then someone else should be able to do it without asking for your permission. Simple as that.
So if I write a piece of software that does the job I designed it for, and you decide you want it to do something else, you should be handed the source code and right to redistribute it? Simple like that?
