In my Not So Humble Opinion oiling a sewing machine that is used once a year is like changing the oil in your car every 100,000 miles. It needs more oiling than that.
Remember, sewing machines do not have bearings, the shafts run in polished bores. Metal to metal. The only thing between the shaft and the bore is a microscopic layer of oil. And it won't last a year if you use the machine any amount at all.
I oil mine every 4 to 8 hours of use depending on what I'm doing with it.
Remember this is just my NSHO.
Joe
Joe