Good question...it's a dilemma that's probably worth a whole additional article.

The short answer is: managers expect to see good visual design, but there's ALSO an implicit understanding that whatever is shown went to production.

If I have 30 minutes to present a study, I don't want to show the visual redesign because then I can't answer questions about the scoping / usability testing / engineer handoff / deployment of it. They could ask "how does a user navigate to this page?" and then if I showed those pages, they'd see there's a jarring visual inconsistency, unless I also redesign those pages.

All of these problems of showing the redesign would be made easier if I had say, an hour. to talk about a project instead of 30 minutes.