Offending people is like vomiting. It can be a necessary and healthy act, but it ought to be a last resort, and most of the time it's an indication of bad health, and people who take a special pride in it* are immature and anti-social. To quote A.P. Herbert:

Nothing is more difficult to do than to make a verbal observation which will give no offence and bring about more good than harm; and many great men die in old age without ever having done it.

*e.g. "Oh man, I got so wasted last night and threw up everywhere!"