Not in Florida.
I've voted by mail twice in Florida and always for Republican candidates who won their races in Florida.
You can look up the status of your mail-in ballot to ensure it was counted.
It's stupid to discourage mail-in voting. It costs us countless votes by people who then never turn up to vote at all.
If you're even just a little bit lazy (and you know who you are) just fill out the damn ballot and drop it in the mailbox.
I have lived in two states that allowed mail in voting and I never felt my vote was not counted. I disagree with the anti-mail in vote nonsense. That is just another conspiracy theory that does no one any good.