Since the turn of the century, the Western Conference has consistently fielded more winners than the East. In fact the West has produced a higher cumulative winning percentage than the East in 14 of the past 15 regular seasons (2008-09 being the exception). In 2014-15 the disparity was an all-time high, as the Western Conference won 56.7 percent of their games while their East counterparts gained 43.2 percent.
As the New Orleans Hornets essentially proved in 2004 when they switched from the East to the West, playing in one conference or the other can be the difference between making or missing the postseason.