Because that’s the logical fallacy of Denying the Antecedent . If “it’s raining” then “the sidewalk is wet”. Knowing that it’s raining tells us something about the sidewalk, it’s not dry, it’s wet. And knowing the sidewalk is dry tells us something, it can’t be raining (because if it was, the sidewalk would be wet).
But knowing “it is not raining” doesn’t tell us about the sidewalk (it could be dry, it could be wet, maybe it rained earlier, maybe a dog peed on it). And similarly knowing the sidewalk is wet doesn’t tell us anything about the rain.
So even if “mo money causes mo problems” all that tells us is that someone with mo money will not be problem free. People with no money might also have mo problems, the syllogism doesn’t tell us about that.
Aristoles’ Nicomachian Ethics (2300 years ago) basically argues that what makes a person “good” is that they are in the habit of doing the right thing. A villain might do a random act of kindness, and a saint may give in to temptation. If you want to be “good” you need to practice being good all the time so that it becomes second nature, or, one might say, a habit.
It’s that carefully developed habit of doing the right thing that let’s others know they can trust you to act rightly, and gives you confidence that even in a difficult situation you won’t be a coward or a liar or whatever. Because you’ve built that habit over countless smaller situations, and it’s a reliable part of who you are.