Do newer generators need to exercise regularly?

I can see only two reasons to run a generator for exercise. One, the fuel needs to be kept fresh, but draining will be even better. And two, some generators depend on residual magnetism to begin generating.

I fuel my home generator once a year for a test run. My Hondas are fueled and test run at the beginning of the camping season. All three are drained of fuel after the test runs. Any more exercising than that is, in my opinion, a waste of time.