Why do desktops start with 992 and not 1024 in Bootstrap?

Question

HTML

Never could figure out why 992? According to
hotlog statistics 1024 - 10 percent of users of
screencast.com/t/K04Isvp1v
768 someone is there
320
360
375
find no devices with 992, why is that?

Answer 1

Browser window borders + scroll take up space.

Answer 2

Damn, I'm sorry, I'll leave anyone else with a question
992 - 16 * 2 = 960 / 12 = 80