Whatever investment that you are doing that doesn't guarantee you a specified amount of profitability in the end is a risk, and  Bitcoin is not excluded from that. Mind you whatever you hear people say about bitcoin getting to certain price level in the future are mare speculations. There is no guarantee that it will play out that way. Also relying on past performances of bitcoin as a proof of future performance is also risk of it's own. So when you have invested in bitcoin and your plan is to hold it for 5 years, that's risk on it's own because you are not guaranteed of making profit. That's why the risk in long term hold is not zero. You can't take speculations for facts!! If you had known the specific amount of profit you will make at the end of the 5 years before investing, then you can say there is zero risk. But since there is nothing like that, there are still elements of risk involved, because it may happen the way you expects or it may not. And it is advisable not to be over reliant on your bitcoin investment so that you don't get into trouble, when your projected time of holding comes and things don't go the way you planned. That you hold bitcoin for 5 years does not guarantee you profitability. That's the risk in it.