I leave mine on if I know I'm coming back to sew soon. Mine has an Eco-mode (with a timer), where the sewing lights go off & the display screen goes dark. I can set the timer from 1 to 30 min. The dealer from whom I bought my machine leaves their display models on all the time during store hours. When mine is off, it is unplugged as we live in the path of some outrageous electrical storms.