[GAMEPLAY] Ingenious Hunter not working as intended

This rune is either not working as intended or its description needs to be more clear.

Rune descsription: Ingenious Hunter ALWAYS READY: Gain 10% active item CDR plus an additional 6% per Bounty Hunter stack (includes Trinkets) REKT: Earn a Bounty Hunter stack the first time you get a takedown on each enemy champion

The problem is: it doesn't give the 10% CDR immediatly, but it waits for you to get the first Bounty Hunter stack. That means that the first stack gives 16% CDR and then 6% after until max cap is reached.

Tried with a bunch of active items, example: Zhonya has 120 secs cd with and without rune and it goes down to 101 secs(120-16% of 120) as soon as you get your first stack of Bounty Hunter, instead of starting from 108 (120- 10% of 120) secs and going down with each stack.