From this 2001 article:
Eric Horvitz... feels bad about [Microsoft Office's Clippy]... many people regard the paperclip as annoyingly over-enthusiastic, since it appears without warning and gets in the way.
To be fair, that is not Dr Horvitz's fault. Originally, he programmed the paperclip to use Bayesian decision-making techniques both to determine when to pop up, and to decide what advice to offer...
The paperclip's problem is that the algorithm... that determined when it should appear was deemed too cautious. To make the feature more prominent, a cruder non-Bayesian algorithm was substituted in the final product, so the paperclip would pop up more often.
Ever since, Dr Horvitz has wondered whether he should have fought harder to keep the original algorithm.
I, at least, found this amusing.
I often (although) not always will upvote a comment simply if it deserves it. I only very rarely downvote or don't vote a comment if I think it is too high but should be positive. Declining to upvote a too high comment is something I do much more frequently than downvoting a too high comment. This is a passive rather than active decision. In general declining to upvote creates less negative emotional feelings in me than actively downvoting something which is too high.
I do sometimes upvote comments that have been downvoted if I think they've simply been downvoted way too much. That seems for me at least to be the most common form of corrective voting.
I have no idea how representative my behavior is of the general LWian.