First, I would look for a fabric that was grown organically, fairly traded, and produced in a sustainable manner that did not use child labor or sweat shops. I would do this for two reasons: first, because it is ethical, and second because ethical clothing is a major market segment now in the fashion industry.
Next, I would consider fabric care. In a globalized economy in which both men and women have active careers, fabrics should be easy to clean and maintain, resist stains and wrinkles, and stand up to the rigors of travel. Business clothing might need to look good after a flight from Dubai to London, a train to Paddington, and a walk to a meeting.
The buyers of high end clothing tend to be health-conscious, environmentally conscious, and active and thus might prefer fabrics, even for business or formal clothing, with a small amount of lycra or other stretch materials that are comfortable for going for a walk or taking public transit instead of just sitting in a car.