Lately there have been rumors circulating about Ripple being listed on Coinbase. This caused Ripple to increase in price, it then fell shortly after. This is a prime example of why you do not buy because of rumors.
But there is something you can do, make a profit!
The easiest way you can profit is if you happen to own the coin, in this case Ripple when the coin rose in price because of the rumors you could, and should of taken some profit.
The second way is riskier. You could of bought into Ripple when you learned of the rumors. You could have then held while it rose and got out before it dropped. This is riskier because there is no telling if and when the drop will occur. You could be buying at the top and then you are left holding the coin.
Some people will continue to hold and buy coins betting on the rumors of something to happen in the future will come true. If Ripple does happen to get listed on Coinbase odds are good the price will rise significantly.
The smarter play is to take the profit when it is there and not bet on the future. The profit that is there is real, the rumors are not a sure thing.
Invest smart, take profit when you can, and you will be successful.