On a door this age, the failure is usually mechanical, not electronic. Extension springs stretch and snap, especially after a cold snap - the climate here runs cold and moderate, and a spring that's been flexing since the Johnson administration doesn't like a hard freeze. You'll hear a bang from the garage, then the door won't budge or it drops fast and uneven on one side.
Cables fray next, usually at the bottom bracket, and you'll see one side of the door hang lower than the other before it gives out completely. Rollers on these older tracks were often steel, not nylon, and after decades of use they flat-spot and bind, so the door jerks or grinds partway up.
If your opener is newer than the door itself - which is common, since a lot of owners replaced the motor once in 50-plus years but kept the original door - the fault can also be a worn drive gear or a limit switch that's lost its setting. That one's less dramatic: the door just stops short or reverses for no clear reason.