Timesheets were made so that managers can be little dickbags and make a big fuss over the half an hour doing something that someone else asked you to do, instead of something they wanted you to do.

Its also a good way to force employees to become their own managers when you arn't giving them work, so you can have more time to sip tea while they scramble to find out how the fuck they will get their hours for this week with no direction being given