I don't know. What if there happened to me some unimaginable pathogen that Earth animal life had no way of resisting, and that multiplied rapidly in the presence of our kind of life?

Extremely improbable. Astronomically improbable. Virtually impossible. All that is absolutely, 100% true.

But given the stakes, similarly astronomically high, I'm not sure it didn't actually make sense to do a quarantine for a few weeks. Yes, I know the indium seals didn't work. But the fact that we failed to create a quarantine doesn't mean it was worthless to at least make an attempt. It cost us virtually nothing in comparison to the stakes.

That's my personal response, anyway, and reflects the opinion I would have expressed at the time if I happened to have been involved in the project.