If I can do one thing different from now on for my product, that will be user test. I regard it as the most direct way to Make sure we come out a product the market wants Resolve many design discussion from the start Identify the right MVP that create value Give guidance to marketing ... ... There are many different types of tests, mainly categorized by the type of question we want to find out as well as the material we have that support these studies. Christian Rohrer, on her 2014 article "When to use which user-experience research", divided all researched based on 2 dimensions: Behavioral V.s. Attitudinal Quantitative V.s. Qualitative Behavioral tests answer the question on "How", how does a user find the a product; how they do a checkout; how they fill in a form; while attitudinal tests focus on "Why", what are the reason you will or will not use a product etc. Qualitative methods are much better suited for answering questions abou...