We all now bitcoin is the best crypto currency in the world and after that ethereum is the best. Then Zcash, Ripple ,Monero these are also good coin.
Well Bitcoin is going down on its marketcap unlike being mentioned above which has great price movement and consistency thats why there is this coinmarketcap to rate the coin movement regarding on its price volume. So basically your profit relies on this matter and not on the top 1 coin in market.