Perhaps ........... you forgot to turn it on???
I'm just kidding, but I found an auction listing on GW for a machine where the poster said they couldn't get it to work. Then they admitted they didn't know how to use sewing machines. The machine in question was a Singer that has an ON-Off switch.
Elaine and I laughed when I said something to the effect ... "Turn the darn thing on, stupid."
Joe