Sobotta recently published 'The Pomme Company', a memoir of his time as director of Apple's federal sales group. During that time Tim Cook ran operations and became executive vice president of worldwide sales.
"Well, for starters, Cook is not a people person," Sobotta writes. "He certainly will not stand behind someone if the going gets rough. He is not that kind of guy. I sense no personal loyalty in him, and I suspect employees already understand that.
Referring to Cook and technology, Sobotta says,
"Technology-wise, I think Tim Cook is a lightweight. I never felt passion for technology from Tim like I did from Steve and some of the great engineers."
Sobotta also felt as though Tim was not a leader.
"I would expect that Tim is having a hard time herding the chickens. From what I saw of him, he was something of a loner. He is not a warm guy nor is he the type to go wandering the halls or Caffe Mac to find out what is happening. His preference is to tinker with spreadsheets and numbers. He is not a natural leader. He's a manager."
Cook has been under increased scrutiny following an executive shakeup that saw Scott Forstall and John Browett leave their posts at Apple.
More tidbits can be found at the link below.