The rule
When you've got something wrong, say so once, clearly, and without adding the word "but". "I'm sorry, I was wrong, and it won't happen again" is a whole apology. Everything added to it is a defence.
Why it matters
Most apologies fail because they're still trying to win. Saying sorry plainly takes the heat out of a situation faster than any explanation, and being able to do it is one of the surest signs of a confident man.
How to do it well
- Name what you did. "I'm sorry I missed your dinner", not "I'm sorry if you were upset".
- Don't keep repeating it. Once is respectful; five times makes them comfort you.
- Then put it right, if there's any way to do so.