Invest 100$ each in top 13 currencies on bitcointalk and just forget that you ever had this money. Wake up after 5 years and open your wallet and you would magically see that you are now a millionaire. Market will boom in coming years and every top coin will boom along with it.
Not true that he would be a millionaire.
Actually, no one knows what would happen in the future as we don't know even what will happen tomorrow. This kind of belief is scary because everyone easily believe others like Bitcoin will surge to the moon next year or people can easily become a millionaire by investing on it for 5 years from now, instead of learning about it to have enough knowledge about how to survive whenever bad things happen or if their hopes aren't fulfilled.