There is a difference between saying the words "I'm sorry" and actually "being sorry". If you are actually sorry for what it is you are apologizing for, wouldn't make sense to not do it again?
The point of apologizing to admit wrong doing. If you admit that what you did was wrong, then it would behoove you to not do it again. Why? Because you just admitted it was wrong.
People abuse the words "I'm sorry". They tend to only say it to get themselves out of a sling. They are getting read the riot act, and don't want to deal with it. So they say those words to get the other person to shut up. Which is way they turn around and do the very same thing they just apologized for, again.
If you're going to apologize, then mean it. Don't just say it to avoid dealing with the consequences of your actions. Forgiveness does not negate consequence.
How "sorry" are you if you are just going to turn around and do the very thing you just apologized for all over again?