Just like stock, you can invest all your money for a coin code if you really trust. But that would be very dangerous. One can make sure that the coin will not fall down to 0 a day.
The advice is to diversify your portfolio. That will help reduce the risk. You do not earn much but if not lost also much.
Well said. If I have my own money I will do it the way like you said. Relying on one coin is very dangerous because you do not have a backup plan. In every business it is very important that you look at all the possivle angles before making a decision.