The central dictum of the lore of wine is that any bottle may be the epitome of perfection under one set of circumstances, but absolutely wrong in some other set. The same applies, in my experience, to whiskey, companions, and songs. When I sing a song that doesn't "work", I try to figure out why. On occasion, I conclude that even though I thought it was a great song, the audience might not share my view. I'll usually try it a few times under other circumstances. If it never seems to "work", I drop it, but if it seems to work in more restricted kinds of settings, I'll keep it for those situations. Songs are a lot like love: they're best when they work for all involved, but sometimes it just doesn't work out that way. (Whew, wasn't sure where to go with that last one)