If you already lose money in gambling I think there is no valid reason to continue because if you do, you will just lose again. Many gamblers dont succeed on their plan to chase their loses, in fact they still lose big money because of thay. Maybe being greedy is the valid reason why people are losing in gambling and that is a sad part.
Greed is one of the biggest problems for gamblers, It will make you a loser even if you are lucky and you started to make so money from gambling. I think people who want to make money from gambling they should stop gambling because it"is not for a long term profit, It's mostly about luck! , even experienced gamblers have a lot of losing bets. Gambling is good for people who know exactly what they want, for people who can control themselves and bet carefully without beting with a lot of money.
So if we are gambling or in online betting, we never expect that we always win and win cause not all the time we are not lucky to have it. Greedy might be a big factor not because they want more but they are having troubles with their losses in the past days, months or years that they really needed to catch for. But in the end, they are still losing.