Grounding is a heavy measure. They're more likely to just inspect other planes with similar doors to see if there's anything obviously wrong with them. Planes

Grounding is a heavy measure. They're more likely to just inspect other planes with similar doors to see if there's anything obviously wrong with them. Planes are complicated machines and the processes for inspecting them are highly detailed. Once they figure out what happened, the fix might be simply to include some simple check for whatever happened. Just another line item for a routine inspection. And probably the list of things to check for doors is quite long already. In any case, flailing your arms and panicking is not part of the process. This incident seems completely unrelated to previous incidents and it happened many years after the first max flew. Which suggests it's an isolated incident. It's quite possible that the door has not been redesigned for the max (quite likely even, because why would they?) in which case they might have to look at all 737s going back 50 or so years.