It's not about "where attention and reason doesn't contribute to success", it's about the simple reality that if someone commits to having something staffed "5 days a week" or "24/7", then either their costs have risen 20% or the salaries have to fall 20% when the working shifts fall by 20%. That might be acceptable to some business and staff (part time employment is already a thing) but magical productivity improvements aren't always as achievable as certain knowledge work fields. More attentive drivers don't go 20% faster or have 20% more space in their lorries, and for that matter I'm extremely sceptical people would pay 20% more attention to the roads working a four day week than a five day one.