Mark Cerny, the lead architect for PS4, was aware of the issues the PS3 was having as a development platform back in 2007.  The system's complicated architecture was making a majority of multi-platform titles worse on the PS3 compared to the competition.

It was then that Cerny began researching the X86 processor as the core of Sony's next home machine.  He successfully pitched his bosses over what the PS4 should have at its heart.

"The biggest thing was that we didn't want the hardware to be a puzzle that programmers would be needing to solve to make quality titles," Cerny told Gamasutra

In 2008, Cerny discreetly sent out questionnaires to developers and middleware engine makers on what they wanted.  The responses he got focused on unified memory, no more than eight processing cores and an easy-to-use tool chain and development environment.

"We wanted our tools to be much richer and much more accessible to our developers," said Cerny, "Even in the launch timeframe."