For ChargePoint, the host pays a (very expensive) yearly maintenance fee and ChargePoint makes sure that the stations work year round.
I am not sure how Greenlots works.
Well yes, ChargePoint will service broken stations. I'm not sure of the financial responsibility. While it's probably true that ChargePoint will
maintain their equipment, repair may fall under the responsibility of the site host. And either way, nothing will happen until the site host calls in the repair to ChargePoint, and in my audit of US fastchargers, I have seen a plethora of instances where a fastcharger is down, drivers show up to the broken station and then contact ChargePoint, whereby they are told that ChargePoint will not take action until the site host calls in the repair, which in most of these cases never happens. In other words, the site host has apparently lost interest in hosting the station and has effectively abandoned it (this leads me to speculate that in fact the repair costs are actually the responsibility of the host, otherwise why wouldn't they simply just call in the issue?)
Greenlots is one step removed from ChargePoint. Usually you have a small regional network (or even an individual host, but this is pretty rare) who is interested in providing fast charging. They acquire the equipment themselves, secure the host sites (or they are the hosts themselves), and then just connect the charging stations to the Greenlots network who manages the back-end: charging station map/app, billing, and real-time availability. If you call up Greenlots with an issue, you will definitely just be told that you need to talk to the host, as they are responsible for all maintenance and repair and other issues. This is not necessarily a bad arrangement, but again, you are going to find a fair share of cases where the site host/network has lost interest in providing the station (or in many cases, has gone out of business) so the station effectively closes.
I don't know how well ChargePoint and Greenlots are about scrubbing their lists. I do come across a fair number of stations that are nominally on both of the networks (i.e. they appear on their respective charging maps), but the stations have been down for 6 months, a year, or even longer, and even in a few cases the stations are even physically gone according to Plugshare checkins. There are not as many of these cases as I would expect, so I do think there is at least a nominal effort made to scrub their lists, but it's not perfect.