I believe he always has been the underdog. The way he looks and it feels he's the only person still at work. More likely he has been bullied a lot and greed? It feels to me he sacrificed himself the biggest part of his life and never been rewarded for it. It's what life looks like if you are a good worker. Abused by your employer and the system. You see them take the profit while you shrink every day a bit more till the opportunity is given to....
The mistake? He better would have kept that black hole and went for the free food and extras. It's like those scammers/hackers taking 5 cents of millions of account over night. It's rarely noticed but together it's a fortune gathered within a few hours of time.