QuickSelect vs. linear search

Question

I am wondering why QuickSelect is supposed to be such a good performing algorithm for finding an arbitrary element out of an n-sized, unsorted set. I mean, when you go through all elements one by one, until you find the desired one it took O(n) comparisions - That's as much the quickselect's best case and much easier.

Am I missing something essential about this? Is there a case the QiuckSelect is performing better, than linear search?

Answer 1

QuickSelect in Average is better in finding the k-th smallest (largest) number(item) in not sorted array