Originally Posted by winger

I rotate rep ranges to keep the body guessing.
See how many reps you can get with 100 kg's and try to beat it, then next workout see what you get with 120 kg's and try to beat that.
Keep the body guessing.

I don't really know what this means but weight pushed would look like this.

12 times 100 is 1200 kg.
6 times 120 is 720 kg.
8 times 120 is 960 kg.

Which looks better to you? Just mix it up and you will keep gaining. ;)