I like the fact that when you upvote an answer to your question, SO reminds you you could also mark is as accepted.
Wouldn't it be nice if the same would apply the other way around, i.e. if when clicking "accepeted" you would be reminded of the possibility to also upvote it?
I saw other questions here on meta that suggest the cases in which an accepted answer isn't worth being upvoted are marginal (i.e. Not having enough upvotes left, the answer being correct but crappy in its form...) but it looks like the majority of the cases are simple lack of understanding of (or care for) the platform by the user.