Assuming we do not use recursion, why is a loop necessary to find an arbitrary node in a linked list

We cannot access nodes in the linked list directly.

Explanation:

In linked list we cannot access nodes directly like arrays. In arrays we have index for the direct access to the element. So we have to iterate over the linked list and search for the node one by one. Since we are not using any recursion so we have to use loop to iterate over the linked list.