Apple's hardware engineering head Bob Mansfield made the mysterious decision to return from retirement only two months after announcing it earlier this year. His choice was at least partially influenced by the exit of iOS software head Scott Forstall. That's according to multiple sources speaking to AllThingsD, who claim Mansfield had clashes with Forstall over his "confrontational management style." Mansfield's return wasn't entirely influenced by Forstall's ousting according to the report, but it was apparently a major factor in his decision to stay on board at Apple.

"It wasn’t a him-or-me situation," one source told AllThingsD. "But, put it this way, I think Bob was much more willing to commit to two more years once he knew Scott was on his way out."

Apple announced Mansfield's retirement as senior VP of hardware engineering in June of this year, replacing him with Dan Riccio. In August, the company and Mansfield seemed to reverse course—Apple announced Mansfield would stay on board to continue to "work on future products" in the hardware engineering division. At the time, outsiders speculated that Mansfield was tempted to stay on by a hefty bonus of some sort—a theory that appears to be verified by AllThingsD's sources. Those sources said Apple CEO Tim Cook offered Mansfield a "massive cash and stock pay package."

But it turns out that was only part of the story. Now, one source claims the timing of Mansfield's reversal "is not coincidental," saying Mansfield and Forstall would not even meet without Cook's mediation. This echoes other claims made earlier this week that Apple designer Jony Ive also clashed with Forstall and that they "would not sit in the same meeting room together." Forstall was a polarizing figure both inside and outside of Apple, and it seems his presence eventually got the best of Apple's executive team.

We can only speculate about how much Forstall's exit influenced Mansfield's return, and it's important to note that Mansfield is still only playing the role of advisor with the hardware engineering team. Forstall isn't entirely out of the picture, either—he's staying on board as an advisor too.