My observation is that downvotes also signify comments that have one of more errors of fact. Of course "fact" is also open to interpretation and not absolute.
You could say "you can only be President for two terms of 4 years each" but someone could dispute that because Roosevelt was President for longer or because in their country that is not the case. Etc.
A downvote because of inaccuracy without a comment isn't very helpful of course.