worst case scenario: never
There is no never, fiat currencies are on decline, and they will be gone in one way or another. People really start to lose trust in them , and just wait until the inflation become worse and worse.
Eventually if enough people start to use bitcoin, it will be an unstoppable juggernaut.
I think a vast majority of people who really like bitcoin have been attracted to it because it offers privacy and anonymity, something which no currency has to offer. The reason I think bitcoin even exists is because it is a way of how transactions are made anonymously, something which could be harmful too but that's the very reason why bitcoin is used, on a larger scale.
I think that only the initial users, most people dont give a crap about privacy unfortunately.
But they will give a crap when the food prices rise tenfold in a year, they will need a stable currency, and all it takes is a google search discover bitcoin.
EXPERIMENT:I wrote in Google: "BEST CURRENCY", and it's on the first page 11th result this article:
http://www.economist.com/blogs/babbage/2011/06/virtual-currencySo it's really easy to find if you look for it, they might not look for it now, but later as inflation hits, they will!
Here is Google Trends:
You can see people tend to look for a better currency than they currently have, and with the forecast they will look more and more for it!
Same with "SAFE CURRENCY"
It's also on first page of google search if you search for "safe currency", you can find easily bitcoin there, and the google searches have spiked in 2015, so i guess bitcoin is growing fast now!
So Bitcoin will be growing dont worry
