Yes that is true, we must be careful in what we are investing eventhough it is cryptocurrency or other investments . We need to know what we are investing and the risk. In cryptocurrency you need to chose the coins and ICO project that you think it id worth investing for and it will grow big.
we should not only be careful about bitcoin or altcoin trading but we need to be even careful about in our day trading, , in fact trading is not so easy as we take it, for becoming a good and successful trader one need to have good trading skill as well as good study about the market and then he can expect to become succeeded in trading.