Let me put this forward with an example...
I was stuck on an SSH issue on my Ubuntu server. I then got a few comments from one user and an answer from another.
I thought that the answer gave me directions in solving the problem, but was incomplete. And once I figured it out, I thought the best thing would be to complete it. So I edited the answer, then accepted it. After all, I appreciate what these two users did I thought they deserved credit for their efforts.
But I was advised to give my own answer. So I did.
So what's the right thing to do here? Do I go with my own answer and accept it, or do I edit the answer of someone else and accept that?