Many people believe that a secure investment is to hold the bitcoins. No, bitcoins is money. Like as fiat money his price has up and down. Bitcoin's drawback till now is the big volatility compared to fiat money. This may be change in near future as the maturity of bitcoin increases over the time. Investments is the same as fiat too. Instead of deposit fiat you deposit coins. The same with withdrawal.
Holding your funds can be profitable only on long term. If the same effects that took place after the 2012 halvings will take place again next year, it means in one year you can x100 your money. For short term profit, you have to get over 10BTC so that a $50 increase would get you a profit of $500..
Needs huge bitcoin to do it and must have huge capital too for get decent profit , but for relay with free way only it's so hard to have 10BTC . You can develop your free money and for sure your money will be increasing slowly .