Wikipedia:Apology

The Remorse of Orestes (1862) – apologies can help avoid an attack of the Furies!

When editors fall out with each other, an apology can often help ease tensions and restore calm and good faith. Even if you do not feel that you have been rude or harmed anyone, you may have given a false impression or contributed to a misunderstanding in some way, and an apology can help to clear the air.

It is easier to demand an apology than to deliver one. We all make mistakes. So take care which apologies you demand, and how often, and what you reject as not good enough. Your turn will come.

Courtesy isn't a standard to expect of others; it's a standard you abide by yourself.

Sometimes it is better to wait for an apology, instead of demanding one. Equally, if you are in the wrong, even partially, it is better to offer an apology before one is demanded. Apologies can help solve problems that are too difficult for normal words to solve.