Because you're just as productive in those 4 days. Same pay for same results. 5 days doesn't make you any more productive.

That's one hypothesis. Why not then 3 days ? 2 days ? Where do u draw the line ?

It's about studies being done as well as being better for morale.

Then why not 2 days?

There is a massive hole in your logic.

Where’s the hold? If we reached a pint where we are as much as productive with only 2 days so be it