I agree that a gambler's lack of understanding and preparation often leads to making irrational choices such as borrowing money just to continue gambling out of greed for winning big.
Only those with a clear mindset and strict boundaries should gamble because if these are not maintained, it’s better to completely avoid gambling to prevent falling into a cycle of debt and regret.
It is not all about lack of understanding. If you don't have to fund to gamble on a particular team which you are convinced that they could win, one can go as far as borrowing money just to play the bet with assurance. Although it's not all bet that needed you to borrow money for you to gamble on them. There are time we ought to let somethings slide so that we can get ourselves. There are still gamblers that would never borrow money just to bet on their favorite team because of the discipline they have as gamblers. Borrowing money to bet can be a temptation but we can as well save money when we have it to gamble emergency games that would worth it, with a good result.
But in the end I think all the actions that will be taken by a gambler do depend on the understanding they have regarding the activity, because logically in any case all the actions that will be taken by a person depend on their understanding, for example they are wrong in understanding an activity then surely most of their actions will also tend to be wrong because you do not know about what is actually and what should be done.
And for the problem of self-control it also depends on how you understand the activity you are doing, because when you do not know what is right and what is wrong then it will also affect your self-control.