That's what i also wonder that how people are busy making lame excuses always when Bitcoin prices are low - "that it's not going to survive and it will be dead" and when the prices are high they say - "we miss the boat" and this will continue as always.
I believe in the theory that these are mostly people who want short-term profits, and when the price is low and relatively stable then they have no motive to invest - and when it is as high as lately, then they wait for a big correction to happen. These are actually very indecisive people, not only about Bitcoin, but mostly about everything they do in life. I know some such people in real life, and I stopped trying to understand them a long time ago - if you've been talking about something for 5+ years and you haven't done anything to make it happen, then no one can help you.