Because man, outside of a sense of the sacred, and a reference point to spiritual potentiality is not sure what human potential means without a religious framework. (and by religion, I'm only referring to Bahai here, simply because that's my main reference point)
If you're not sure what potential human beings have then you cannot empower people to reach that potential. Most of the time non-religious empowerment programs simply create self-centredness (or at least the ones I've observed anyway)
