It used to be somewhat common for websites/services to go down for a few minutes every so often for maintenance/migrations/etc.

Tech entrepreneurs should give no weight to this. The market seems to support engineers doing on-call rotations, and a service that can’t tolerate any downtime is (theoretically) a service that is worth a lot to a lot of people- which is perfect for monetizing.

Tech entrepreneurs should stop giving excessive “nines” of availability. Even 99% is probably enough for most customers to never notice, and significantly easier to engineer than 99.999….

The issue is less giving out excessive SLAs - it’s more that even a tiny ass startup thinks they need high availability and four nines and scale to billions - when in reality almost no one actually needs it. But those are cool engineering problem so we’d rather work on them than on building a business.

It's still common. Nobody really cares if a site is offline for a few minutes. You try again later (or not, but so what). Heck, nobody cares if they are offline for half the day, it gets fixed and at the end of it it's just a post-mortem for the nerds to read and a shrug and life goes on for everyone else. People vastly overestimate the importance of anything that is on the public internet. None of it is life-critical (if it is, it certainly should not depend on an internet connection or a web server being up).

> and a service that can’t tolerate any downtime is (theoretically) a service that is worth a lot to a lot of people- which is perfect for monetizing.

The connection makes sense but one must not think in this order. One must think “people will pay for this” and then consider “does this need to be highly available?”

If you have more than one road to choose from, and one of them doesn’t require high availability, then give that one some bonus points for that.