Actually the analog meters do go out of calibration ,, you see they have magnets inside that slow/stop the rotation of the mechanism (braking magnets) , and when they get old (or damaged by lightning or whatever) they typically start reading HIGHER than they should ... a common way to lower your meter readings is to place a STRONG magnet on the side of the box... also those screw adjusters you commonly see that are labeled F and S (fast / slow) they indicate the METER is FAST or METER is SLOW ... if you crank the “SLOW” adjuster you SPEED UP the meter..
Exactly right. My company also refurbishes old analog meters, and I have seen the ladies on the line calibrating these.
The fact that analog meters can get out of calibration (moving parts again) is yet another reason electronic meters will soon be universal. E-meters use a single crystal for timing and a single precision voltage reference for both current and voltage measurements; neither get out of calibration.