Here is one of my this hurt experience that happened today. Today working as a cashier I found a low serial number $5 (IOG 0000666), it was the first time I found a low serial number after a customer gave it to me a cash transaction so I put it in the cash register so I could get it later in a isolated spot but later when I was trying to get the bill I realized one of my co-worker gave it to another customer as change.