I don't like giving reasons anymore because they're usually a lie. I don't write up a list of pros and cons and find there's only one con and that's the one true reason for not wanting to do it. Reasons are complicated and hard to know yourself. By saying it, the other person can find a way to show it's not true, or get another reason out of you which shows your first reason wasn't complete. People have sometimes used my reasons against me - "remember that time you said you did X because of Y?, Now you're saying Y wasn't true, so you were lying back then!" They miss the fact that there are multiple reasons, and they aren't binary ("I want to" and "I don't want to" can both be true at the same time!) and I miss the fact that I cherry pick reasons that seem placating and omit the reasons that might seem rude.

It's not rudeness, but honesty that makes me dislike giving reasons. Sometimes I give the reason "I don't want to" which seems about as correct as I can understand.