Even if it's slower for the vast majority of cases, but there are rare cases where the computer would otherwise freeze, that's still a win.
And in many cases it's assumed to be small, but not guaranteed. That's where the trouble lies.
A classic example is Windows using a quadratic algorithm for arranging desktop icons that caused severe performance issues when users had many icons on their desktop.
https://github.com/microsoft/Windows-Dev-Performance/issues/...