Disagreement is generally the reason. Disagreement can be about many different things. Some folks might disagree with what was written in a comment. Some people might not understand what was written in a comment. Some people might be having a bad hair day. Each person clicking on the down vote button might have a different reason for doing so.
As a personal rule, I never down vote comments and I never down vote threads.
For example, at the moment my comment to the OP about having a good eye has seven down votes. Chances are a great many people viewing this 'after' image don't appreciate what I see in it, so it's easy to click on a voting button. Someone might think I was being facetious with my comment and click on the down vote button.
I also don't necessarily feel good when one of my comments gets 100 up votes.
-8
u/johngpt5 2d ago
Good eye.