Why invest your hard earned bitcoins when you can just hold them and use that as your investment, got to be safer than any other investment opportunities.
yes that is right to say that only holding bitcoins for a long time is also a good option you do not need to invest your money anywhere in present time and by only holding it you can make good money.
But there is no assurance that the price of bitcoin can be increase more in the future because the price of bitcoin is not stable increase the movement of the price of bitcoin still relaying on demand and supply.. if bitcoin is not in demand and more people are selling it the price could be decrease or crash. so be careful with your decision. well for now we are seeing good movement of the price for long time bitcoin holder we can say that they already got good profit and the growth of bitcoin is slowly increase that can make you profit if you wise use your investment into trading the rankings of altcoin and the price are changing if you can see the list of coinmarketcap the top 20 are good choice than ICO 's or new releases altcoin....