In the world of cryptocurrency, everyone wants to make more than 100% in one transaction, but this is not possible over the course of a long trade. You can never sell coin at the very top and buy it at the very bottom, and then greed will kill you on a certain day.
We should not really consider it luck, we have option to choose which coins and were the one to decide where and when to put it so better try until you make it work and profitable.