Please read before you buy mishi/ hisha

I bought this pet a couple of days ago and tested it, to my surprise, the effect isn't what i had actually hoped for. I do have more rerolls from it but i don't get a lot more locks or better items than before i was using hisha, in fact, on some runs i get less. So as i read on and think about it, i finally understood the nature of hisha's /mishi's ability: 10% increase in reroll chance just means you get to reroll more but rerolling at say 100% luck and rerolling at 50% luck will give you the same effect in terms of items. So the only difference between 100% luck and 50% luck is only the number of times you reroll, but the items you get will be the same as long as you reroll. Hope this clarifies