A fairly simplistic answer to a perhaps far more complex question
Those years ago when PoET was pre-revenue, those pie in the sky, "next big thing", instant riches fueled speculation and that kept the SH afloat.
Now that PoET, in the age of Denselight, is post revenue, there is no revenue at the moment, so, as Benji points out, we are trading at our "value".
Throw in the understanding of retail shareholders of how irrelevent thay can become and how easily their "investment" can be devalued by a PO and you have our current trading price and volume.
I think PoET will, in time, become a name in the semiconductor world, but the world will need time to test drive PoET when it comes online, and decides if this is the one.