Innovation can be defined as anything that reduces the cost of a transaction.
It has been years since I washed my car in a self-serve carwash bay. Usually I get a carwash with a gas fill-up or go for the full detailing when needed.
Since today was a warm, sunny day I decided to try the self-serve carwash route. In the past, I'd have to bring singles and use the change machine to get quarters. Each quarter might buy me 15 seconds of wash time. The problem was I had to guess, ahead of time, how long it would take me to wash my car. How long was enough? Four minutes? Six minutes? It was either a race against the clock or money down the drain.
Nowadays, credit card readers are places I never considered five or ten years ago, from smartphones to parking meters; and, of course, at self-serve car wash bays. Much like Car2Go's pay-by-the-minute rentals or Amazon's pay-by-the-hour servers the self-serve carwash bays now let you pay for only what you need. Just swipe your credit card and turn the dial from pre-wash, to soap brush, to rinse whenever you're ready. A much better UX.