No, but it holds different weight for different people. It means much less coming from someone who always screws up and has to say it a lot than from a person who is genuinely and sincerely apologizing for a mistake.
No, it just may be harder for people to accept them.
Better late than never. Always apologize when you know you've done something wrong to another person.
Well sorry is usually said after something's been done so I guess it's right on time.
nope its never too late