But I wonder why they don't just ask instead of jumping to a conclusion? They often reject the app for simple reasons these days. And they are often wrong.
They have no time to do it.
And it looks like the reviewer puts himself in a basic user shoes.He will not read any user manual but checks if the UI is straightforward.
Visibly he did not feel so. So he may not be wrong but just a bit exacting.
Remember also that if a user gets confused for 10 seconds with an app, he will just discard it. So it is your best interest to make it as easy to understand as possible.
For this, IMHO, @darkpaw, is right.
Topic:
App Store Distribution & Marketing
SubTopic:
App Review