Do you have to clear all cache after unpublish, making changes and republish?

I have one observation. To do something as modify a single CSS line from the theme I created I had to uninstall it, reinstall it and clean cache. Is this meant to be process by design or am I doing something wrong?

Sorry! I seem to have overlooked the php artisan theme:install function.

I updated the theme information in the theme.json but how do I install it? I thought publishing was the same as installing it. Do I need to put it in the Marketplace?