I agree, but it is not easy to explain on the home page of the program. Maybe with a little pop-up text when the cursor is on the icon.
1 / Update (or install) then clean the traces of what is old and outdated that installers / uninstallers left.
2 / Delete a version (or all versions) then clean the traces of what is old and outdated that installers / uninstallers left.
3 / Update the signature database
4 / Miscellaneous