This question often arises; here is a possible answer.
We are embodied beings — that means the entirety of our lived experience (the ‘stuff’ of experience) has an embodied aspect. In the current culture of over-emphasis in visual representation (think adverts, icons, TV, screens) over actuality, we tend to equate whatever is in our conscious mind with our ‘reality’. However consciousness has only limited access to the totality of our embodied experience. Movement, touch, performance, time-based endeavor, etc., have complex ways of engaging that which lies in our haptic or embodied experience, both the familiar and that which is latent or remains to be discovered. Art forms and practices that engage more comprehensively with these factors tend to have more humanistic results. Another factor is that we have been taught to focus upon what we think of as the ‘rational’, whereas in fact the body has only its multiplicity of sensing surfaces, interior and exterior, with which we encounter the world. Everything else including concepts and actual perceptions and their meanings is built upon the workings of that interface. Since materials and their various qualities- behavioral, tactile, weight, sticky, alive etc., are what we encounter, air- stone- heat- wet and so on, you could say that our entire sensory domain is and has been formed by material interaction. So continuing to work with materials is a thoroughly rich knowledge- and experience-based experimental domain that taps into other forms of intelligence, memory, the intuitive etc. Before we can design or create, we need to discover, experiment, play, communicate, question, attempt, and do. The more of our faculties we bring into that process the richer the experience.
That’s why we make things.