Rarely is revenge noble or even handed. But it is always sweet.
When I was 16 my first boss told me I was useless to the point of unemployable and that I should quit or be removed. But by the time I was 18 I had taken her job from her, and left it a year later to join the military.
It’s wrong to tell young people they are worthless, and sometimes dangerous. You never know who they might grow up to be.