Profitable usually if you buy before it is listed on a good exchange. After it is listed on any exchange, the profit you may make depends, even loss is possible if it is hyped too much before getting listed.
For the new coins listed on the Exchange, it will increase if you are on the big exchange as Binance, Poloniex, Bittrex, Houbi ... also need to create good news along with many other factors to help the new coins can increase. These require a professional and experienced management team in the cryptocurrency market.