Because as we can see it is growing in value, so as long as you can still afford to buy bitcoin grab it, because sooner or later it will grow double of value of what we have now.
The use of Bitcoin will intensify every day.
More and more people use the Bitcoin as currency, experts predict, which should propel its price towards new heavens. See what the experts tell us:
http://geldquelle11.blogspot.de/2017/11/einstein-money-machine-discovered.html