Calibration and self-test are 2 different features. During the calibration, the UPS goes on battery until it’s fully drained, this way it can know how long it can truly last on batteries. Most of the times you don’t calibrate your UPS unless you’re suspecting an issue.
A self-test on the other hand is just a quick test (less than 5 minutes) where the UPS goes on battery and check that everything is OK with the battery, the voltage, all the sensors etc.