In order to make something work, it's important to reciprocate. So people say, you need two to tango. You can't tango alone, can you?
Then, there's the proverb, two heads are better than one. Imagine working in a team where the members take passive roles - no contributions, no ideas, no feedback. Zilch. You'd be sitting there alone, making a fool of yourself, initiating discussion that'll lead no where. Frustrating indeed.
Ergo, it's only fair that each individual at least considers the other party as every good turn deserves another. Isn't it also rude then to not reciprocate? Well, at least that's what I think.
However, there would of course be occasions one might not want to reciprocate at all. When the other party is dubiously annoying, how can one possibly reciprocate? Or if you can't seem to agree with the ideas thrown to you, it might perhaps best be ignored.
What about you? Generally speaking, do you reciprocate?