I have mentioned multiple times in past here that people should be cautious with alt coins. If some coin has moved up like 100% or more in just 24 hours, it does not mean that you should also purchase the coin. You should first understand the reason behind prices moving up. Then, you should also analyze the benefits and demerits of the project.
Some traders or investors who get late when the price of that particular altcoin hasn't reach 100% are very lucky though fewer in number compared to the majority who bought at peak when the price is on reversal mode basically it's due to their inability to analyze and made research about that particular altcoin, for instance I was lucky to read the recent XRP court case a Sec which ripple won consequently triggering a massive pump on it price, I bought at the middle of the price rally and sold at high, actually the reason for that massive pump was because of the case won by XRP, there are other more examples we are to kept abreast with latest news on any altcoin to be traded.