Its not a communication overhead, it's that business owners want to maximise their returns on their fixed operating costs subject to the 5 day limit. One extra staff member in a traditional office is extra software license, extra seating, extra hardware, extra HR/payroll/insurance, extra risk, extra training etc etc.

Remember to thank your unions for the weekend.

▲

whatshisface an hour ago | parent [-]

If it was utilization of fixed capital that motivated the maximum-length workweek of today and centuries past, they wouldn't mind who was on the shifts or how many so long as there were three of them.

	▲	majormajor an hour ago \| parent [-]
		I'd be surprised if the jobs where it highly matters which employer covers the shift weren't significantly outnumbered by the ones where it generally doesn't. Labor-as-a-commodity has been an explicit goal of a lot of industrialization management methods.