There's definitely some true to that. If you don't know what you are doing, set aside couple of bucks each month, throw darts at printed crypto coins list and invest accordingly. With turbulent market like crypto you'll gonna hit a mooning or two sooner or later. I know it sounds like a joke, but I mean it.

However, once you get the hang of trading it becomes similar to chess game. You can't ever predict what is going to happen - you are right about that, but you can move to better strategical position, that might not pay off within an hour, but it might prove to be a solid move couple days down the road. E.g. short lived Altcoing/BTC shorting.

If you'll ever want to learn more about trading, this guy does a pretty good job at explaining it: http://tradersfly.com/