What matters most is the transparency of the design and the process of bringing it to life. The final product itself should easily reveal its story to the viewer: what materials were used and how it was put together. Hidden structures and layers of different materials should be greeted with some caution. They can leave room for unpleasant surprises, and all you can do is hope that everything has been done correctly. However, when the design is transparent, you don't have to just hope for the best because you simply know it to be right.
Objects that have been designed well should make you think: "Of course, why didn’t I think of that!" They seem so obvious but are far from it - cleverly concealing the complex design and production process that has taken place. Like a true masterpiece.