Plugin Compatibility Before Installation

Plugins also may crash with other plugins, causing incompatibility issues. (global)

Plugins can be integrated, meaning that they work in sync. They may not interact at all, or they may be incompatible, meaning that your website can’t function properly with both activated at the same time.

Therefore, it’s important not to install plugins without some consideration first. 

For instance, sometimes your theme does handle some basic functionality for you, such as adding the Facebook Pixel or Google Analytics tracking code. Some people will install a plugin for that (and even one plugin for each) when they currently have a theme that handles it for them.