It’s also possible that there’s an issue with the switch’s connection. Ensure that all cables are correctly connected and that the switch is fully functional.
I don’t believe it’s a switch issue. I can hear the hum shift as I change speeds. I removed the light kit to examine the capacitor. The fan started working again when I got a new capacitor. A new capacitor has arrived. I’ll replace it the next time it doesn’t start. Until then, ‘if it ain’t broke, don’t fix it.’
Is it easy to spin by hand when it’s turned off? Try spinning it by hand when it’s on and humming. Is it going to take off and spin? If this is the case, your capacitor may be defective out of the box (a rare occurrence), or it may be the incorrect capacitor. If it doesn’t, or if it doesn’t spin freely as it should, the motor or bearings may be defective.