Is Banning Broken?

I ask this because i just got a six minute ban for a game that says it was on 12/15/2015 (Today’s date is 12/14/2015).

The more major point is that i got banned for idling which i rarely do (as in this is the only time i’ve done it on halo 5 because i had to go #2 and the game doesn’t let you back out). Even if it happened in this one game, in this one instance, why was i banned? Does the system just automatically punish you even if its your first offense. Or was it counting those rare times where it has taken me 5-10 seconds to start playing because i looked at something on the dashboard for a second and couldn’t hear the game starting (because it mutes the game). I’m confused.