Spare capacity

People are expected to work at 110% at work. The modern work culture
demands this.

This, to me, is dumb. People should work at 90%. Most bosses in
corporate companies might be shocked at the idea that their staff work
at less than their maximum output.

This point is something complex and related to human resources theory.
Biascally be like a boy scuot. Plan. Be prepared. Life always fucks
things up. We need the spare capacity to deal with it. That isn't
available when everyone is worked at 110%.