For my money there's nothing actually wrong with implementing, say, a level 1 API, as long as you don't claim anything higher. It'd be very nice for everyone to be at level 3, but obviously the tooling isn't there yet to support it universally.
I hadn't seen it before, but I like it. Practical and specific. I think you could actually use this when proposing time/cost estimates for web service development.
For my money there's nothing actually wrong with implementing, say, a level 1 API, as long as you don't claim anything higher. It'd be very nice for everyone to be at level 3, but obviously the tooling isn't there yet to support it universally.