The ‘Why’ part is perhaps the most important aspect of a user story. This links to the sprint goal which links ultimately to the product vision and organisation’s vision.
Lately, I got reminded of the very truth of this statement. My youngest son is part of a soccer team and they have training every week. Part of the training are exercises that use a so-called speedladder.
After the training while driving home I asked him what he especially liked about the training and what he wants to do differently next time. This time he answered that he didn’t like the training at all. So I asked him what part he disliked: “The speedladder. It is such a stupid thing to do.”. Although I realised it to be a poor mans answer I told him that some parts are not that nice and he needs to accept that: practising is not always fun. I wasn’t happy with the answer but couldn’t think of a better one.
Some time passed when I overheard the trainers explaining to each other that the speedladder is for improving the ‘footwork’, coordination, and sensory development. Then I got an idea!
I knew that his ambition is to become as good as Messi 🙂 so when at home I explained this to my son and that it helps him to improve feints and unparalleled actions. I noticed his twinkling eyes and he enthusiastically replied: “Dad, can we buy a speedladder so I can practise at home?”.  Of course I did buy one! Since then the ‘speedladder’ is the most favourable part of the soccer training!
Summary
The goal, purpose and the ‘Why’ is the most important thing for persons and teams. Communicating this clearly to the team is one of the most important things a product owner and organisation need to do in order to get high performant teams.