Common Courtesy
I get a lot of good advice at this Forum, and always try to thank the person taking the time to post an answer or suggestion.
Even the guy that said my name "said it all" and I didn't know what I was doing.
Even though I may not be thrilled with the attitude or advice given, or the manner it is delivered, I'll take the time to thank the poster for bothering with me - just as I would an instructor at the field.