The number one reason to flag content is disagreement on rewards. Below are the listed reasons for flagging. Click on the flag and you will see for yourself. Thanks,
Flagging a post can remove rewards and make this material less visible. Some common reasons to flag
Disagreement on rewards
Fraud or Plagiarism
Hate Speech or Internet Trolling
Intentional miss-categorized content or Spam
I see that. Have to say I disagree with lumping a simple "downvote" in with a "flag".... they're two very different things.
Actually, they aren't
In most platforms, they are. Flagging a thing is flagging it... usually some sort of inappropriate content/spam/kiddie porn/racism/threats/etc. The idea of flagging is it raises awareness on a method of filtering content. Be it a manual admin, or an automated system like we have here where it actually hides the content from people/feeds/etc.
A downvote is "I didn't like your content or have a differing opinion." Not "your content is abusive and should be removed."
In the white paper disagreement on rewards isn't even mentioned