The in-game descriptions provided by the developers are not:
Grammatically correct
Spelled correctly
Objective
Informative
Consistently Structured
Oddly worded
In lieu of these low-quality descriptions, which take up valuable space in the UI, they either be temporarily removed until they are satisfactorily made or permanently removed given that they offer no meaningful information pertinent to the gameplay.
This is by no means an exhaustive list, and some screenshots provided apply to other categories, as well.
Vehicles are another can of worms
Sometimes you get a history lesson, sometimes you get a brief description of the gun, sometimes you get no description, and sometimes, the description is basically the gun being compared to something that already exists without any additional context.