Also doesn't "tack on the end of the array" imply allocating new memory and copying the whole array? It might make sense for a linked list, or a self expanding

Also doesn't "tack on the end of the array" imply allocating new memory and copying the whole array? It might make sense for a linked list, or a self expanding list whose backing storage wasn't full. Even then there is the cost of pulling the end of the array into cache up front.