4 days gives an immediate benefit that is not as relevant for fewer days. It gives you a regular weekday off. That means you have a day off to go to the bank,

4 days gives an immediate benefit that is not as relevant for fewer days. It gives you a regular weekday off. That means you have a day off to go to the bank, go to the doctors, call customer service for a bunch of companies that may not otherwise be open on the weekend, etc. Further, the weekends carry an expectation of doing something. Such an expectation would not exist for the weekday off. If we do move to a mass 4 day workweek, this obviously implies that the 3rd day off should not be the same for everybody, so basically it shouldn’t be implemented by just making Friday another day off like Saturday and Sunday. It would be much better if that 3rd day is divided for all employees between Mon-Fri.