Even I, a designer, do not know why a certain proportion feels dated or why another one feels exciting at a given moment. I leave that to the cultural historians and theorists.
Good design in my view takes the best from the past and transforms it into something fresh. The dynamics and proportions of a great piece of contemporary design correspond in a mysterious way with attitudes of the moment, as well as with tendencies in other fields of art and design.
My only period of rebellious dressing was the 70s, when I remember wearing a snakeskin coat by Ossie Clark. Aside from that, my rebellion has consisted of designing the clothes I wanted to wear, which were non-existent on the womenswear market.
I like to think that I have taught Uniqlo how far a "basics" company can go in the direction of quality, style and modernity. For my part, I learned how to design the best possible collection with limited resources.