Limit access to the WordPress admin panel for your clients. Block functionality like updating plugins and viewing menu items for administrators, while
A very extensive admin panel with many options your clients don't need can be reduced to a clean admin interface with all your client needs for maintaining his website.
Hiding specific menu items from your clients admin interface is as easy as checking some checkboxes.
If you have a plugin that is essential to the core of your website, you don't want your clients disabling that plugin.