Tech Radar spoke with Jed Ashforth, senior designer at Sony Computer Entertainment Europe, where he dropped quite the shocker. The DualShock 4's light bar was designed from the start to support Sony's virtual reality headset, Project Morpheus.
"The tracking light… it was our department that said we need that on," Ashforth stated. "It was for tracking for VR."
Sony's VR team made sure that light was put into the controller, as Sony evidently had VR in mind from the start. The main purpose behind the light bar had to remain hidden until Project Morpheus was announced at GDC this year.