Actually we couldn't say that it is pure luck cause everyone  knows that profiting in Bitcoin is a serious thing it will need more discipline and self control.  Like what other said above those investors buying some bitcoins before when the value is too small and hold it until date then one thing for sure they will partying cause they made a huge profits.  But like what I said it's too difficult cause there's a chance that the temptations will almost hit them they almost sell their Bitcoin. But they can manage their self and then now they got a big profits.