Can someone please explain to me why if you use two identical tires everyone says that the front needs to go backwards......not as the same orientation of the rear one.....why?

 

Explained here:
http://cyrilhuzeblog.com/2009/08/23/...by-avon-tyres/

It's the force against the tread splice. But - then it's mounted against the water groove direction, so if you use the same tire on both ends, one way or the other you'll sacrifice a bit of safety. I'd say the tread splice is more important. Since the same size tires are made for both directions by most manufacturers, if you're buying new tires, it makes sense to get the ones made for each end.

 

The greatest loads on the rear are while accelerating, on the front while braking. Many years ago it was routine to use the same tyre on both wheels and that was conventional wisdom. For many years now, just as for cars, most bike tyres have been designed for either one or the other wheel. Study the treads for those!