There is one vid of a guy on YT talking about his daily drop off in power. Turns out it was 1 small cable shading out one small part of a panel Which was enough to shut the whole panel down. His conclusion was the way they were wired up caused it to stop working due to the shade on one set of cells.
That's because it was wired with a single inverter for the whole string. So it can only generate power based on the weakest panel.
Instead you can use micro-inverters by each panel. Or optimizer's which are dc-dc converters and basically do the same thing.
This is very common when you have a chimney, and the shadow from it moves around.
I think installations where it's all on a single inverter are not very common - a cloud moving in the sky will mess with the entire array, it's just not a very good way to design it.
