I have different point of view tbh, I will not focus on how much I may lose as well as the potential win but I'll focus more on how to manage my money.
Too much focus on how much you may lose will not good as it will bring negative mindset mindset and can be something stressful for some people.
If you focus on how much you will lose, that means you will focus on how to manage your money that you are using to gamble, having gambling budget and not using more than what you can afford to lose. So this makes me not to completely agrees with you. It is good to focus on how you can lose for you not to fall victim of gambling loss.
It's better to focus on how to win and be positive for it helps to see better choices while you are already in a situation.
But if you have not started gambling yet, it's best to just not gamble and just wait til you have some extra to wager. I know it's very tempting to just wage a big amount to win a big amount but when you know you have no such amount. Just be with the small amount and maybe try the parlay to win big.