Understanding the problem is part of the design process. Good design solves real-life problems. “Making products look good” is important, but only one small aspect of design.
Design (or synthesis) is really just a theory — a guess at what users actually want. Until you put a product in front of real users, any design is just a theory. Synthesis is iterative design and requires testing and revision.
I agree designers need to understand the problem, but my advice is: don’t spend too much time understanding the problem before you start designing. The goal should be to get something in front of real customers as quick as possible, then begin iterating.
You can spend 10 years thinking about a problem from every angle and still produce a product no one likes.