That is how it is by default. Personally, I only rank my mirrors 1-2 times per year.
The hook only runs when the mirrorlist package changes. Basically, when we add or remove mirrors.
You can skip it entirely. pacman/alpm has this functionality built-in. You can inhibit the hook by putting an empty file or a symlink to /dev/null at /etc/pacman.d/hooks/eos-rankmirrors.hook
Alternatively, you can uninstall the package eos-rankmirrors and pick a mirror manually.