Belial232
Each bottleneck is a subsequent gate and the length/power within the channel is multiplied at each level so the starting level which is 0 would have a power of 1 while level 1 would add 2 to your power level and level 2 would add 3 and level 3 would add 6 it's an exponential growth. The stages are like major realms in other cultivation systems. I won't say much about this yet as the story hasn't shown this yet so it's a surprise.