With whom is it best to design the interface? With a designer or frontend developer?

Question

Design

I am at the prototyping stage of the project. I feel that I need a person with whom I can consult in terms of UI / UX, how best to arrange the elements so that they are convenient for the end user, how to easily display a lot of complex data. Your opinion?

Answer 1

With a designer.

Answer 2

Answer 3

Of course, it is necessary to talk about convenience and performance with a "techie" and not a "aesthetic humanist", most likely it will be a programmer, but often people do not do their own thing.