Why does Mayweather have bad hands ?

Paper Cuts Mayweather's hands are bad due to chronic paper cuts from constantly counting his money over and over again

Floyd's dad also had weak hands Floyd does do exercises that strengthen his hand muscles and I used to see him with the wrist grip at pressers to strengthen his wrist and forearm as well http://www.mightyfighter.com/wp-content/uploads/2013/02/floyd-mayweather-hand-grip.jpg

Have good form

I don't think he wears gloves while beating woman.

Been fighting since he was a kid, wear and tear plus genetics I guess.

It's been said he used to punch the door knob as a kid, and no I'm not making that up.