That's usually in hindsight? And I said it wasn't obviously insane to them, not that it would pencil out in the end.

Can also just be an asymmetric bet - relatively small outlay with low chance of working, but massive upside if it does, such that it's still positive expected value.

But mostly, I think all these armchair quarterbacks should not have very strong opinions about something that they almost certainly don't know much about compared to the people who build these. The person I responded to cited a random blog that ran some numbers, and includes such gems as "In space, a broken fan or a fried motherboard is a crisis." Just... lol