Well, let’s be realistic rather than idealistic. We all see apologizing as a good practice, however when the time comes when we really need to we will find thousands of reasons for an escape. In case, we don’t find any then we will try to create one(s). In relation to human behavior, I guess It has something to do with the egoism that is built in ourselves and lucky he is the one who can overcome it.
As for you sister Malika, it would be really a great deal for you to bring that word out of your husband’s mouth and it will be more rigid for him to do so when confronted with advices and lectures on “how good it is to say sorry”. Actions speak louder than words. Try to get back to him and say sorry even when he is wrong, sometimes that would melt that ego and enlightens him but don’t hold me responsible for the result 