Witts End numbers and description are terrible

So witts end works exactly like this you will do 15 magic damage on hit till level 8 At 9 goes up 10 a level so at 9 you do 25 till level 14 where you hit 75 . Now it changes to 1 a level at 15 2 more at 16 then back down to 1 a level maxing at 18 . Now my issue is it says does 15-80 magic damage on hit but it does not say anywhere it won't scale till level 9 this would be fine if it was not league but no item in the game literally works like this but witts end now not even summoner spells they all scale a small bit a level . Be nice if the item's description would say in the shop how much it did at the level you currently are like it does once you buy it only reason i know how it works is I like to test things in the tester map otherwise i would be hella confused in game why i was still at 15 damage at level 8 .