What does real delegation involve?
Three parts, and most men do one.
Give the outcome rather than the method, so there is something to aim at.
Give the authority to decide inside that outcome, including the right to be wrong in small ways.
Then stay available and out of the way, which is the part that takes actual discipline.
Why does it usually fail?
Because the owner hands over the task and keeps the decisions.
The man comes back for permission. The owner reads that as not being ready, when it is the system he was handed working exactly as designed.
The second failure is impatience with the dip. Every handover costs quality for a while. A man who cannot tolerate that takes the work back, and now he is paying somebody to watch him do it.
What should be handed over first?
The thing you do most often that requires the least judgment.
Not the hardest thing, and not the thing you hate, which is usually hated because it is ambiguous. Frequency plus low judgment is where the hours are and where the risk is smallest.
Write it down once while doing it. That document is the handover.
How do you know it worked?
The work happens at a standard you can live with and you stopped thinking about it.
Not perfectly. At eighty percent, consistently, without you. Eighty percent done by somebody else beats a hundred percent done by a man who has no hours left, every time.