Gap's CEO is right. In a recent Wall Street Journal story, Gap's CEO, Sonia Syngal, said fashion is an art AND a science, a right, and a left-brain skill. And therein lies the problem: it's a rare skill not found in the larger fashion businesses that for decades used large merchandise planning systems to decide their buy, only to be disrupted, out-category-killed by Amazon, which can run 200 a/b tests per minute to learn what will sell. Running a business that's art & scienc