Bitcoin was launched in 2007. It's 10 years and still no country has approved Bitcoin ?? 
and in 2018, 2nd richest man "Warren Buffet" said "bitcoin will end up badly"
and in 2018, 2nd richest man "Warren Buffet" said "bitcoin will end up badly"
Bitcoin has already approved and legal in some countries like Japan, Australia and England. Regarding to the Warren Buffet's view on bitcoin, being expert in one field doesn't mean his point is valid on anything (in this case, bitcoin).