Why do people resist those "we need to talk" talks? Is avoidance good for a relationship?

I recently asked a question about how people feel when they hear “we need to talk,” and a lot of people answered that those words are words they kind of dread. It makes them feel like they did something wrong, among other things.

I’m wondering why people resist these talks so much. I know I do, too. They feel quite unpleasant, I guess. No one wants to be beat up on. On the other hand, shouldn’t those talks clear the air? Shouldn’t they solve problems and make things better? Shouldn’t they improve our relationships?

I guess I have to wonder now. Maybe having those talks doesn’t improve things. Could they make things worse? Could it be a good strategy to avoid those talks and hope the problems disappear on their own?

Do those talks work, in your experience? If not, why not? If you avoid those talks, does that work? If so, why do you think that works? Perhaps avoidance is good for the health of a relationship?