How is the labor intensity of inserting an element into the center of an ArrayList evaluated?

Inserting an element into the center of an ArrayList has a time complexity of O(n), where n is the number of elements in the list. This is because, after insertion, all elements to the right of the insertion point need to be shifted to make space for the new element. For example, if inserting into the middle of a list of 1000 elements, approximately 500 elements will need to be shifted one position to the right.