What is the practical benefit of betting you landed in the worst spot? When computer scientists talk about Quicksort, we regularly talk about it being a O(N*Log

What is the practical benefit of betting you landed in the worst spot? When computer scientists talk about Quicksort, we regularly talk about it being a O(N*LogN) operation. But by this logic, we should be treating it as N^2. That doesn't make sense, because in practical applications, we generally are dealing with random inputs, not adversarial inputs. I'm not convinced what a lay-person is interested in solving matters. We're talking about Bellman, who is a mathematician and well known for attacking problems relevant to computer scientists. A lay person would just bring a compass and call it good.