The company I used to work for switched to 4-day weeks during COVID and everyone was much happier, especially those with children or other caring responsibilities. Productivity was the same or better.

But, predictably, 2021 rolled around and they forced everyone back to 5-day weeks. The justification given was ‘some’ people weren’t always taking the extra day off. No figures given, no other reasons.

I, and everyone else, strongly suspect it was just C-suite not liking the idea of people getting the same pay for one day less.