This lag can lead to slower write speeds than what your SSD is otherwise capable of. The TRIM command keeps this from happening by ensuring your SSD always has plenty of pre-cleared blocks available.

Enabling TRIM Support While Windows 7 users have the benefit of having TRIM enabled by default, as long as a supported SSD is present, I don’t believe any current Linux distribution does the same. Yes ...

Apple has begun enabling TRIM support in its latest OS update if you install a third-party SSD -- but be advised, some SSDs don't work with the chosen method of TRIM.