Mark Root-Wiley explains why navigation menus that appear on click rather than hover are better.
I like the fact that it calls out that:
When you first make this change, it’s true that some visitors might still expect hover menus. They may even say they prefer them if you ask.
But then goes on to provide some rationale (ammunition?) from various big guns on why click menus are better.
From the US Web Design System:
Avoid using hover to expand dropdown lists. Hover is difficult for some users and won’t work on touch screens. Dropdowns should expand on click or with keyboard navigation.
From popular frontend framework Bootstrap:
What it really boils down to is user intent. The purpose of a hover state is to indicate something is clickable (underlined text). The purpose of a click is to actually do something, to take an explicit action. Opening a dropdown is an explicit action and should only happen on click.