> revenue wouldn't be lost if you had a 100ms outage

If that little blip cascades briefly and causes 1000 users to see an error page, and a mere five of them (0.5%) to give up on purchasing, boom you just lost those $700 (at least in the travel industry where ticket size is very high). Probably much more.

So I invest all that time deciding where, when and how to travel and don't press refresh when I see an error which is more than likely on my end?

An error page can be enough for a handful of customers to decide to “come back later” or go with a competitor website.

If you think about experiments with button colors and other nearly imperceptible adjustments, that we know can affect conversion rates, an error page is orders of magnitude more impactful.

It doesn't scale linearly.

Indeed, so arguing that if revenue is 24m a day that a 1 hour outage loses 1m is wrong

Arguing it is $1,000,000.00 is wrong.

Arguing that it represents the order of magnitude of potential damage is cogent.