If you switch off everytime you leave the machine you have to reset your stitch size and other setting when you switch on. I leave which ever my machine I am using on during my working time, going back and forwards to it. I switch off noting settings when I have finished for the day.
I worry more about switching iron off so I just turn that down to no heat when I leave it during working session.
The on off switches I feel only need on when you start and off when you finish.