The incentive requires the chargers have 97% availability.
I think that is the case now, but I don't believe it was necessary before 2023.
I don't understand how once you've installed it you can't just set a price to charge that makes it profitable to maintain, whatever that price is.
Possibly at that price there’s not enough demand. Put another way, it’s possible there’s no price that covers the cost of maintenance per charge and attracts enough people to get enough charges.