When is it too early to ground an aircraft, (i.e, how do you know that you're jumping to conclusions or not)?

If two brand new airplanes fall from the sky (and the crew from the second flight were, as I understand, instructed about the first case’s faults), and I was the owner of an airline, I think I would ground them, just until its clear if the two disasters had the same cause.

Here is an expert who agrees with that:
http://www.pbs.org/wnet/amanpour-and-company/guests/mary-schiavo/
of course ground, since the whole point of grounding it till you know what happened and get it fixed, (err on the side of caution).

Isn’t it amazing that in so many cases, people have to die before some action is considered “cost effective.”

The airline industry historically has been one of the best modes of transportation that polices itself and government regulates this also. The seriousness that has been taken in analyzing crashes and changing standards is unparalleled in my opinion. If suddenly this is being treated differently that is a huge disappointment, and the question in my mind is why is this being handled differently? Obviously, money is part of the problems in these matters.

It seems to me there is reason to suspend using these planes, I assume even though the planes are still flying in the US that they are investigating what happened. I remember there being a big scare about DC10’s when I was a kid. I also remember flying on one during the scare. My dad liked the wide bodied plane. I don’t remember all the details when that was going on.

I personally would be hesitant to get on the Boeing 737 Max 8 right now.

Thank you. Here’s the latest news.
https://tinyurl.com/y2r6ennz (737 max news Google)