Why does ssh key authorization sometimes fail?

Question

SSH

I need a script to be executed from one server on another, I decided to use key authorization in ssh for this.
ssh ip-address ./script.pl
Everything works fine, but sometimes, for some reason, authorization does not pass, but asks for a password. If you click a few times, then it diverges and works. But such glitches spoil the entire operation of the mechanism, has anyone encountered this?

Answer 1

Try to run at the time of the problem:
to see what happens in fact.

Answer 2

The problem was that the user had uid 0 as root, and when you log in as root, sometimes you get under this user.