I would put them in risky investment list. When we select an asset to invest the market cap should be prime requirement to consider. It has to be reasonably very high so that we can have proper on going trades with it. For example, in situation where we need instant selling or even buying the order has to be executed instantly. If there is wait time until it gets fulfilled then it can go south. Ask a day trader how this works when it comes to highly volatile crypto currencies. By the time your order gets fulfilled the value may change its course and it could either fill your order or it could so away from your expected order execution price that it may never get filled and we may need to just wait or sell in a losses. So cap, prime target.