Cash handling and robbery risk
Tills, banking runs, opening/closing with cash on site. You'll know to keep the till light — that's not the part that needs saying. The part that's easy to miss is that a robbery is planned around your routine, not your takings: the same skim time, the same banking run on the same morning, the same one person cashing up after dark are what make a target worth casing. Varying the pattern isn't paranoia — it's making your shop boring to watch. And if it happens anyway, the only thing in the shop that isn't replaceable is a person — personal safety comes first, ahead of the cash and the stock.
This is one hazard. Your register is the set that applies to you — under 20 questions, about five minutes, free.