I thought the movie "Yves Saint-Laurent" was very interesting. Saint Laurent was not only a designer, but also an artist. With his talent, he would have succeeded in any region that has anything to do with design. The movie begins with him announcing his retirement, spoken with words that he must have thought of deeply beforehand. Saint-Laurent continued to reign the fashion world for nearly 50 years as the creator of 'mode'. He passed away not long after his retirement, in 2008.
The quote that impressed me the most in this film was Saint-Laurent saying "Fashion is dead", just before his retirement in 2002. He kept up with the trend of the time (i.e. safari look, smoking style, Mondrian dress etc.) and he continued to give great influence to the fashion world. But the fashion designs started to change in the 1990's, which started to change Saint-Laurent's feelings towards fashion too. (This was when Japanese designers such as Yoji Yamamoto and Rei Kawakubo started to participate in the Paris collection.)
Saint-Laurent became chief designer of "Christian Dior" at the age of 21. After leaving Dior in 1962, to allow convalescence after a nervous breakdown, he established his own label "Yves Saint-Laurent (YSL)" with the support of his partner, Pierre Bergé. Bergé was a sharp businessman who knew a lot of politicians. Berge and Saint Laurent were two as one.
Fashion business is a tough job. The crucial difference with designers in other design disciplines is that you have to continue producing new items twice a year for the annual collections, no matter how much of a slump you are in. Another difference is fashion is relatively unaffected by "innovation", when compared to other design disciplines that deal more with products or architecture.