Breakers/mysteries/corpses cause additional time, Affecting the speedrun to be longer than previous speedrun.
When breakers pop to their lower tier (all of the breakers going from example: breaker 2 > Breaker 1) previous run the wave would begin to go to the next wave. This also follows with mysteries where if the mystery phase pops into whatever pops out the previous run would end, when all mystery bodies were popped, todays time if the entity that spawns from the mystery is still alive the wave doesn't end until defeated, concluding additional time. And with the new changes to the game for some modes, this affected Hardcores death animations for some enemies, where if they die and have a death animation, one that lasts a very long time instead of the instant death and fall than disappear, some fall and become corpses that cause the wave to not end until the corpses despawn contributing more time on the clock than previous submitted runs.