Bitcoin is not a good idea as a currency. Although Bitcoins goal was to become a currency, Bitcoin now looks more like an investment product than a currency. Its dramatic price fluctuations are not conducive to being a medium of exchange.
If the price of bitcoin keep increasing people involve with it. As we're watching the price which is decreasing and people are quiting. Just think what if the price increase instead of decrease i am sure no one will left the bitcoin even more people join it and invest there money.