You’re falling into the trap of cognitive bias if you truly believe it has to do with a man’s wealth.
There are surely just as many wives of poor men as those of wealthy men whose wives cheat.
Either way, no single answer will ever accurate explain the reason for ALL individual cases.
Most of the time, it is not because they need more money.
They probably need more love, more fun, they want to experience sex in a new dimension.
They might not need more money
They might not be getting enough attention from their husband is either he's not always at home from one trip to another
Or maybe they don't get sexually satisfied by their husband that's why they flirt
Simply because sometimes there partners only care for their money, they forget that they have a partner that needs some love and affections too. Sometimes we are blinded of the things that will make us happy for a short time. We didnt notice that we are hurting our wife.
We must understand that our wife stays at our side when we have nothing, so dont leave them when we have everything.
Money is just a thing , it will not give you true happiness. its better to spend your money to your family. They will not leave you until you dont have money.
Love your wife and family more than your money.