Success that makes you meaner wasn’t a promotion. It was a trade.

Getting more does not automatically cost you anything, but it often does, and the bill shows up as a change in how you treat people. Impatience with anyone slower, sharpness at home, a shorter fuse for whoever needs something from you. If that arrived alongside the win, something was exchanged rather than simply added. A trade can still be worth making, though you ought to know you made one.

The people who knew you before will spot it first, so make it easy for one of them to say so. Ask somebody honest whether you have got harder to be around lately, and resist arguing with the answer.