-1 from my points after downvoting another person's answer

Question

Good day , community !

First of, I love askubuntu and the community here seems to be so much more friendlier than on other sites ! good job, admins ! As for meta , it's my first time asking a question here

I've a small question. On this answer I've downvoted new user's answer, which clearly doesn't add anything to solve the problem. At the same time, I've got -1 from my points. This happened once in past, too, but I've brushed it off since i was in a rush.

Could someone please explain why does this happen or point me to the appropriate post with this rule outlined (if it is a rule and not a glitch )?

Answer 1

From the help center:

What happens when I vote down?

When you vote down, you are nudging that content "down" the page, so it will be seen by fewer people. Voting down answers is not something we want you to take lightly, so it is not free.

• Downvotes remove 2 reputation from the post owner.

  - Downvotes on answers remove 1 reputation from you, the voter.

• Downvotes on questions are free. (Why?)

• ...

^{(emphasis added)}

Downvotes on answers cost you 1 reputation point. This is to prevent abuse (i.e. mass downvoting). Don't let it stop you though! Downvoting bad answers is very important for filtering the best answers from the bad ones. If the post is later deleted your reputation will be returned to you.