Have you ever had a misunderstanding with someone and when they went to apologize it just didn't feel like they meant it. Or have you made a mistake and sincerely tried to fix it and the other person just didn't seem receptive. And maybe that you recognize a different form of apology as sincere than someone else. The more we understand about how to express apologies in ways that others will recognize as sincere, the better we're able to also identify sincerity in others.
https://www.5lovelanguages.com/store/when-sorry-isnt-enough