“When people show you who they are, believe them the first time.” -Maya Angelou
Contra: The famous athlete caught cheating, says, "I'm very sorry; I wasn't acting like myself." The cruel adolescent after smearing a person's good name, "Nah, man, I was only joking."
There is always a place to apologize, confess a wrongdoing, and say, "This is not the person I want to be." Such a response is more credible. It affirms our actions reveal our character. It is who we are. But it acknowledges we fall short of the moral bar, and we are willing to accept the consequences of past actions and the sacrifices necessary to never repeat them.
If you've been wronged by someone, be leery of empty promises. Wait for change.
If you keep doing the same thing, don't believe your own hype, this is who you are. God can change you. There is hope at the cross.