that is the risk when you invest, you dont know what will happen to your investment especially it will run for a couple of years it is good if you will became a millionaire by that year but also you should look the in the moment when you will have nothing to earn from your investment, 5000$ is a huge amount so people must think of it before putting in an investment that there are no assurance of having a positive profit.
While many people here have huge faith in bitcoin and I include myself among those people, the truth is no one knows exactly what it's going to happen, for example someone that invest in bitcoin could think that he is making a very safe choice but if in the future a new coin appears that is so good that makes bitcoin obsolete then you're going to lose your money, while I know that what I'm describing is very unlikely it is not impossible, so there is always a risk whenever you invest your money.