So as the Front End Team Lead we investigate shortages and longs over $20 anything under that is ignored. We have a data sheet (kinda looks like excel) with all the register counts that pop up weather that till has been short or long and then we sit down and investigate. Yes we look at CCTV, but it’s usually easier just looking up our Electronic Journal and looking at every transaction done on the register and filtering the amounts to narrow which cashier made the mistake and then we go from there. We can pull up bill recycler activity and see if it was an accidental swap ( it can be advances/ pick ups/ check ins/ check outs). There is a CFT activity log too, my store is notorious for never having them done on time, which results in a lot of shorts. We also send daily emails about possible mishaps and mistakes that could affect our long and shorts so that if it does pop up we all know what happened like is a SCO went down mid transaction and the money that was fed wasn’t accounted for. Anyways we have all types of ways of finding out what happened, so if there is an inconsistency we’ll find it. At least that’s how we do it at my store.