From the experience of last couple of years, if you mean to get profit, you should know when to buy and when to hold. Just holding for long time won't make you rich. What now be bought by 1$ can't be done by 2$ after 10 years.
Based on my very own experience, long time holding is a best way to do when you really want to have more profit on selling. Holding and waiting until the price goes up and selling your coins and tokens is a good idea. The price will actually increase because the demand of coins and tokens increase also, so the people will patronize to buy although the price is very high.