Because it's a piece of ***, that's why. I used to own one that I thought I was getting a good deal on, and it was probably the worst motherboard I've ever had the misfortune of using.
It has a hard-wired compatibility problem that means it gets hung up by basically ANY high-performance or even moderate-performance RAM, and it leaves you NO workaround because adjusting ANY of the timings and voltages will also cause it to lock up. It has a well-known problem with the sound controller that I have seen dozens, if not hundreds, of people post about on here, and there's apparently no fix for that either. It sucks for overclocking (that much should be obvious, since it's an Intel board), and its durability is pretty questionable. On top of that, they market it as an "Extreme" motherboard, which is about as far opposite from the truth as any statement I can think of.
Basically, everything about that board is terrible. I went against my rule of not buying Intel boards because I found it for a great price ... but I am never buying another motherboard from that company again.