Why should I create an itinerary for an experience?

Gretchen Rubin has made a compelling case that the four stages of happiness go from anticipation to savouring to expression and then reflection: https://gretchenrubin.com/happiness_project/2007/04/the_four_stages/

Ensure your customer is off to a happy start anticipating your experience by sending them an itinerary that gives them a few details to look forward to. Hopefully the itinerary you create will also help them think through some logistics of your experience ahead of time. Your customer may choose to share the itinerary with other friends they’ve invited to your experience so they can anticipate it too!