I have mentioned before how we had a bad visit to New Orleans.  Usually I give a place a pass after one visit, but I really have zero interest in returning in this case.  And yes, maybe I should, but I won't.
It's best when you have a "local guide", a friend who has lived there and does live there.  I know here I could take you places and you'd think this is a S-hole, and other places and you'd think "This is much nicer than I expected."  I suspect that is broadly true.