Trading and Gambling travel in the two different directions. One is Hard work and another one only on luck. One is if you not follow carefully there is chances of loosing your investment another one is if you not even carefully chances of loosing what you invested.
Both are risky but chances of gaining in trading is high if you wait patiently but through gambling it is one shot game there is no need of choosing another option for winning through gambling. I hope trading is best option who are looking for long term holders.
You are correct that in trading, you will only lose if you sell the alt coins that you have bought. If you continue holding it and if the price will go up again, you will have the chances of gaining profit as long as you wait and patience really pays off in crypto trading. Unlike gambling and especially to games that are based on pure luck, it is really a one shot risk thing.