I lost money in the last bitcoin crash because I bought right before it all went downhill.
It's obvious people aren't using bitcoin to shop, but instead using it as an investment.
In one quick moment heard mentality will respond by "cashing out" their bitcoins for money (something that is actually accepted and can be used to by things) and this will create a chain reaction. One by one everyone will flip out, won't want to miss out on their cash, and start purging their bitcoins for ever lower numbers until the currency is devalued.
There will be another crash, people will forget or think "things will be different this time", and will once again start building the next bitcoin bubble. I think I might actually buy some during the crash when they're real cheap. Every year bitcoin's popularity rises and more people get suckered into it.