I have several machines, my Janome 6260and Janome 1600p are used several hours almost daily. I've made it a habit for years to have both tuned up after Christmas EVERY YEAR. Never had a problem with either of them. $40.00 each annually is a small price to pay to keep my workhorses in tip-top shape.
The other machines are cleaned and lubricated regularly by my son or myself.