In my experience, creators tend to overestimate how much clients care about what you do, how you made that thing, or what went into "getting it just right". Here's my simple rule for myself especially in the early stages of building a client relationship, not just in instructional design, but any kind of work:
Don't just sell what you do. Sell the outcome of what you do.
You don't just create training content in Adobe Captivate; you optimize patient care by keeping critical skills up-to-date.
You don't just produce marketing videos; you tell stories that convert prospects into leads.
You don't just design UX; you bring joy and quality-of-life to the mundane.
(Of course, tailor the stated outcome to the client's actual end goal.)
No one buys what you do. They buy solutions to problems. Sell their future state as a result of working with you.