eBike technology explained

Hey everyone!

I've been riding my eMTB (a Specialized Levo SL) for about a year now, mostly on some pretty gnarly trails, and it got me thinking about the tech that makes these things tick. Specifically, when we're troubleshooting issues, how much do we really need to understand about the internal workings of, say, the motor controller or the battery management system (BMS) versus just knowing the symptoms? For troubleshooting purposes, what's the most crucial piece of eBike technology you think riders should have a basic grasp of? Is it the motor type, battery chemistry, or something else entirely?