~there is always some risk to place money in Bitcoin or hold them in a fiat savings account. Because bitcoin is volatile. Don't place your whole money.
High risk means higher returns. That's what applies to Bitcoin investment. Volatility in Bitcoin isn't something scary but it is a potentially bigger profit. If you don't brave enough just keep your money in a fiat savings account. Indeed don't place all your money in Bitcoin, but it doesn't mean just put a small amount of money is the right way.
You can keep some money in Bitcoin for long term investment. Then you can get profit from it.
There is no guarantee for profits even you keep your Bitcoin in the long term. The point is how the strategy in your investment. Also, how good you analyze the right time to "buy" and to "sell'. That requires knowledge to predict and analyze the market trend of Bitcoin. It is better to start investing once you have already enough knowledge about it.