And ndriscoll is also unfairly generalizing. Which usually happens when you generalize because it's impossible to take all eventualities into account.

For example, I've worked on add-ons to other software. But it's cloud and you gotta make certain calls back to your "host" app. Said host app responds to most calls in more than the 150ms they claim is the max. Because of what guarantees our plugin makes to the user and despite us caching whatever we can we need to make multiple such calls to make our guarantees... well guarantees.

So what can we do? Of course we show spinners while we make those necessary calls and make absolutely everything we can get away with async.

But we can't get away from things potentially taking more than a second when something isn't in cache, the host app is slower than usual and under 150ms is impossible for anything that doesn't just hit our own database.