It's the structure of the program. There are 10 and 8 set phase for volume accumulation, then 5s and 3s for increasing intensity.
Probably easier to understand if I just post a screencap of the program instead of trying to explain.
https://uploads.tapatalk-cdn.com/201...43cf43ff6c.jpg
However, I am running what's called Inverted Juggernaut, which flips the sets and reps during the 10s and 8s blocks, and puts mandatory rest restrictions in place. The idea is to keep technique and explosiveness up while still getting in volume to increase work capacity, because most people's last few reps tend to get ugly as shit once fatigue sets in.