If you ignore them, then you never know when they stop working. Really. The fact that they look the same working or not is one of the problems with them, and

If you ignore them, then you never know when they stop working. Really. The fact that they look the same working or not is one of the problems with them, and why you really do need monitoring and someone to pay attention to the monitoring at least every few days. I spent six years in the utility-scale solar PV industry. You would be shocked to learn how many of the panels are not working in any given array. I've seen everything from almost 10% of the strings not even being connected to the inverters in a utility scale array, to a shocking number of rooftop arrays that were producing nothing. In my entire experience with the company and all its customers, we never encountered a single utility-scale array that was fully working when we arrived on site to add our monitoring or optimization systems, and many of those were brand new! In one case of a sizable array on the roof of a Texas energy provider here in Austin, we discovered the inverter had died years before we discovered it! (This was field testing of of inverter bus noise effects, and the oscilloscope showed nothing but what the wiring picked up as antennas!) Turns out no one ever looks at the power bills in a power company... :-) Solar PV actually requires a fair amount of maintenance for both prevention and remediation (cleaning and/or replacing panels, repairing connections/wiring, combiners, inverters, etc.) to ensure they are actually operating, but most owners are happier to cover their ears and eyes and sing, "La, la, la..."