I have no idea why this is in the game, but basically, if you are ahead in Conquest and have more points, and the enemy team takes more flags, you will bleed tickets at a faster rate than normal to even out the points. Meaning you can hold all the flags all game, but the enemy holding them for a fraction of of that time is enough to balance out the score. Because this kicks in after a certain point in the match, there's no reason to play the objective until the match has passed that time threshold.
There's no reason for this to exist. Winning due to it feels cheap, losing due to it feels like you were robbed. It just makes me stop playing because it creates frustration and removes the satisfaction of actually having a comeback.
If a comeback mechanic needs to exist, it needs to be based on gameplay mechanics, like Behemoths were in BF1, or it needs to be done by just playing the game, like in BF4 where you did not bleed tickets as long as you had more flags.