If you lose in gambling them it should be that you are not interested in winning or you are only for the fun. We all need to make money that is why many persons spend their time to forecast game so they can have good winnings that can cover their previous loses. Some gamblers are for the fun and in another way round they need the money also they can be good at what they do and have fun as well.
So far I have never met anybody who can work for a living as gambler. I know some guys who are successful in gambling and made some money, but never enough to cover all their living expenses from it. In my eyes they are still recreational gamblers. From the Internet I know that there are people who managed to become millionaires through gambling, that is such a small percentage compared to the total number of gamblers.
I wouldn't say that anybody who loses in gambling is not interested in winning. Ask any gambler to choose between winning and losing and everybody will pick winning. You can have fun in gambling when winning and losing, it shouldn't be only about money. Because there will always be a time when we lose, even if we spend all our time forecasting games we can be wrong from time to time. Winning consistently is one the hardest thing in gambling.