Earlier quoted context omitted.
There's quite some distance between "infallible" and the kind of failure mode CS's error induced. Be that as it may, I don't think the question is about infallibility, though. The question is, was the software fit for the purpose Delta used it for? And the follow-on question is whether CrowdStrike sold it for the purpose Delta used it for.
Fair, but certainly that's the responsibility of the purchaser, no? CrowdStrike couldn't feasibly know how all their customers utilize their software. That's the end user's responsibility. Software fails, machines fail, we all know this. The technical leadership at Delta should know this. Do we think software vendors should be responsible for ensuring their customers safely deploy their software? I can't imagine that…
When it's priced differently depending on how the customer plans to use it, and it's sold only through a consultative process, I'm not sure it's so clear. In order to determine their pricing, the sales team demands to know how the customer is using it... so they absolutely arguably do know.