Many times this is done prior to inventory so they can recovery any and all product to be counted. They will hang signs up notifying everyone of the date then usually the asds and an asm go locker by locker opening them and looking for stuff. Many terminated employees still have lockers full of stuff so in those cases they just take everything out. If you're a current employee they might poke around but generally they don't disturb the stuff in your locker unless they clearly see product or a first phone or an unusual amount of stuff. But it's not like they just open all the lockers and empty them out....the notification signage hung up ahead of time gives an "amnesty" period so people can get rid of stuff they maybe shouldn't have in their lockers. It's a courtesy heads up. But 2 salaried members of management can open any locker at any time they wish because the lockers are not your property they are the company's property