It’s an exciting time for the Glasgow-based BBC Scottish Symphony Orchestra, which has just extended the contract of its popular music director, Ilan Volkov, and will shortly move into its new permanent home in the heart of the city’s entertainment district. “By any yardstick, then, there is everything to play for in the orchestra whose technical ability and reputation has utterly transformed in the past decade and a half.” So why is the orchestra’s longtime general director choosing this moment to walk away?