For this very man greed was his problem £20000 is a huge sum that can afford a very lucrative business. Giving such huge amount on gambling shows his high level of greed and people of this kind can do anything just to make money not minding if it's legal or not. I wish he recovers soonest because this can cause a man to commit sucide.
But we don't have the same thinking as him, just as what happened. He became addicted to gambling and we can understand his situation that those who became addicted recently, they're more for the risk and they're more for the profit and they won't think that it's going to be ending with a bad result. What's bad is that if he hasn't recovered yet he still pursues his addiction and that's hard to stop.