This User Interface (UI) Designer position correctly states that UI designers create navigation maps, functional specifications and design requirement documents. Hint: They don’t code anything.
Yet a recent polling of my colleagues and clients shows that the common usage of “User Interface” person means someone who does "front end" (interface design) and the "back end" (programming). There are many UI Designers out there who design the usability and they have a background in the area. However, because programming is being conducted simultaneously, many people fall into the “split-mind problem”. It is hard to focus on the user's needs while thinking about the system's needs.
Years ago, before working exclusively in usability, I programmed in C++, C, HTML, Java and some virtual reality and artificial intelligence languages. I can verify that there is a huge mental leap between the "front end" (interface design) and the "back end" (programming). It is extremely difficult to do good usability if your focus is code.
Takeaway: Be careful to clarify your conversations with an agreed definition of UI Design skills. In the usability community, it means the above (see ad). In the programming community it means the job involves code. There is a difference. Make sure you know what you are hiring.
Part 2: Focusing on strategic insights
Fact: Usability is not Quality Assurance (QA) and can not be performed professionally by a Quality Assurance specialist. Would you have your plumber take care of legal problems?
People who hire “Usability Testers” and QA specialists to handle usability requirements, seem to think usability is purely functional. They, like the authors of the above (second job ad), contribute to a one-sided view of usability, namely that usability is purely a tactical step in good software development.
Usability is actually highly strategic. Design changes can impact: markets pursued, how audience segments are defined, whether marketing and business goals are altered, whether resources need to be allocated to change or add new functionality etc. Compare this to the outcome of QA where fixing a button, moving a link or adding an image might be the result.
Takeaway:If your usability requirements are going to be covered by QA, you may be missing the forest for the trees. Never substitute QA for usability in your web development lifecycle.