My own damn fault

I have this bad habit of when someone comes in and buys something I hand them their change and say thank you. But after today I'm going to count every bill into their hand. Today this 6 foot tall man with a tattoo on his neck claimed I didn't give him the right change when I know what was in my drawer and what I gave him. It's my own fault for not counting the change into his hand as I gave it to him. Live and learn but karma will come back to him. Its just another reason to get my video camera's set up.