User Research
Making assumptions can be useful for building a hypothesis,building bases, and testing assumptions.
Constructing the context of the intended use, want, or need of the experience the benefit of user research. Each phase dealing with the user allows a chance to collect data.
User testing
Finding how users interact with the current device, app, or interface is key. That way I can study the problem in context and determine the scope of the project and framework to start constructing my solution.
Card sorting, A/B testing, and running through the existing app, website or similar apps assist in honing down on the users needs and creating the best user experience.