[Jensson]

> the cost which often gets quoted with those mistakes is not a real cost

It is still money they would have made that now weren't made. It is very important to explain to people how much value is lost during these events so that we also correctly value the work to prevent such events in the future.

[kqr]

You're comparing "reality where accident happened" to "an alternate reality where everything is exactly the same but the accident did not happen" and this is not a sensible comparison.

The reality we have produced the accident. You can't have that reality and have it not produce the accident, because it was set up to produce the accident. Proof: it produced the accident.

To avoid the accident, you need an alternative reality that is sufficiently different so as not to produce the accident, and some of those differences may well have resulted in lower profit overall.

(You may argue that you're able to set up an alternate reality that does not produce the accident and results in higher profit overall – that's a completely different argument, but it also requires you to specify some more details to make it a falsifiable hypothesis. Without those details we can not guarantee a higher profit in that alternate reality.)

[furyofantares]

And to add to that - the number is almost always wrong because people tend to just count the money hose throughput times the downtime. But many of the people who would have spent money on the downtime will do so later. I guess maybe that's not true of advertising revenue? Although I imagine advertisers tend to have some monthly spend.

[dalmo3]

Sure, the probability that things that have happened will have happened is 1.

The real test for hard determinists is being able to conclude that the probability of things that will happen is also 1. At that point there's no such thing as "falsifiable".

[ta1243]

If your shop takes $3600 an hour in revenue, but there's a problem with the till which means that people can't pay for 10 seconds, you haven't lost $10 in revenue, you've just shifted revenue from $1/second to $0/second for 10 seconds and $2/second for the next 10 seconds.

[mikepurvis]

Yup, the only "real" cost there is a customer who decides not to buy after all, or buys elsewhere instead. But that's pretty unlikely, especially for short outages. And it's even less of an issue for entities with a lot of stickiness like social networks (Facebook, Twitter) or shopping websites with robust loyalty programs (Amazon Prime).

[User23]

It's also hard to understand because it's largely illusory. If, say, Facebook is down and ad spending ceases for an hour, that money didn't just go up in smoke. It's still in somebody's ad budget, and there's a very good chance they're still going to spend it on ads. Thus, while there will be a temporary slow down in ad spend rate, over the course of the quarter the average may be completely unaffected due to catch up spending to use the budget.

[toast0]

It's hard to track, but there's a lot of factors.

Some usage (sales, ad views, whatever) will be delayed, some usage will be done somewhere else, some usage will be abandoned.

But costs are likely down too. If there's any paid transit, that usually drops during an incident. If you're paying for electricity usage, that drops too.

And significant outages can generate news stories which can lead to more usage later. Of course, it can also contribute to a brand of unreliability that may deter some use.