A delegated task should come with enough time to do more than imitate the last person.

Handing something over at the last minute guarantees a copy rather than a contribution. With no room to understand why the work is done that way, the new person can only trace over what exists, including the parts that stopped making sense two years ago. You get the previous version again, slightly worse, and then wonder why nothing improved.

Delegate earlier than feels necessary, with time built in for questions and one wrong turn. Say explicitly that they are allowed to change the approach. Then ask what they would do differently, and treat the answer as the reason you handed it over rather than as a complication.