Plus there is all the fudging ..
.. to make it appear no rules on working hours are broken.
Many (many many) moons ago I worked for a company who had a timecard system that automatically blocked any registration of overtime. Billable hours were logged in every which way, but anything at cost to the company could never have overtime - irrespective of reality.
Naturally, sticking to the hours you were actually logging was grounds for negative performance evaluations yet no, you didn't get payed because they were not in the system.
So I left.