Apple will often automatically download installer to /Applications directory.
If we want to upgrade to mojave when the machine has sierra and it may have high sierra installer and mojave installer, the high sierra installer will stay on the machine.
If we want to upgrade to high sierra when the machine has sierra and it has high sierra installer and mojave installer, the machine will upgrade to mojave.
It seems that it does not happen reliably.
In order to reduce uncertainties, I decided to delete unnecessary os installers.
Apple will often automatically download installer to
/Applications
directory.In order to reduce uncertainties, I decided to delete unnecessary os installers.