Solar panels and accompanying equipment break. Itβs much easier to maintain a centralized installation than having people need to travel for service.
Home thermo solar (solar water heating) sometimes breaks (pump...) but a home setup is so simple many owners can repair it themselves, and nearly all can easily find a local serviceman, a competent plumber can tackle most problems.
As for photovoltaic a home system seems very robust to me, even serious hail cannot damage it (some windshields will break under it way before the panels!).
I completely fail to see even a single and most prominent problem.
In a sunny geographical zones there usually are many user, and a is local service offering.
Moreover energy produced by solar panels in homes is locally consumed, therefore there is no maintenance (nor any non-neglectable cost or loss) related to distribution (they are non neglectable).