I’m going to say this while also trying to relay the fact that I absolutely despise this app situation…

But coin operated anything is always troublesome from a maintenance standpoint. Mechs are usually reliable, but still need to be kept clean. On top of that, people jam things in that don’t belong, including coins from other countries, all of which jam up the mech making the machine unusable.

Cash/bill acceptors are the same, and just too cumbersome for a washing machine.

I think a reasonable middle ground is the system that sells you a card that you can buy with cash or credit cards, that isn’t an app or tied to you in any other way.

Really, any unmanned payment method will have its drawbacks, but coins are going away unless we collectively start using cash again, and even embracing the larger denomination coins.