Let's say you do 4 sets.
The first set you can do 12 reps.
The second set you can do 10, then you do 2 negative reps until you get 12, just like the previous one, so 10/12.
1st set is 12
2nd set is 10 and 2 negative reps
3rd set you did 8 reps, you do 2 negative reps to get to 10
4th set is 7 reps, so 1 negative rep until 8

1st set - 12
2nd set - 10/12
3rd set 8/10
4th set 7/8

Long hair = health, virility.
Bald/balding = disease, unhealthy, ugly.
When you see an animal shedding fur, you automatically know it's not healthy. Humans aren't that much different.