Perhaps you need to read the World Economic Forum's "Top 10...

Perhaps you need to read the World Economic Forum's "Top 10 emerging technologies of 2015 ". You can google it. At No.5 is: 'Additive Manufacturing ' which includes 3D printing.
In my personal opinion, 3DM is sat at the threshhold of a huge growth area for the 21st century - printing replacement human parts. That is why I am in 3DM. I work in the health service. I can see the future staring me in the face, with this company. It is a long term investment, not a DT dream, or even a short term trade.
All the above is my personal opinion. DYOR.