I can see how a subscription model would be appealing if it was in lieu of outright buying expensive equipment. Operating expenses for some machines are cheap but the machines are expensive enough that the tests themselves are expensive to pay off the machine.

Of course, the reality is more likely that the hospital still has to buy things and the subscription is a net loss on top of that so patients (or the people paying for the care) are screwed twice.

Or the equipment is otherwise expensive up-front to a small clinic. Ophthalmology, for example. The subscription feature is cheaper than becoming a financier.

It also creates a HARD dependency on internet access.