From Wikipedia:

[Tim] Cook graduated from Robertsdale High School. He earned a Bachelor of Science (B.S.) in industrial engineering from Auburn University in 1982, and his Master of Business Administration (MBA) from Duke University’s Fuqua School of Business in 1988.

Nowhere there does it say “Computer Science” or “Programming” or “Development”. Cook is a master of supply chain management, and Apple’s current success is defined more through the meat and potatoes of production than it is about the glitz and glamour of the iPhone’s design or operating system.