We can't say with surity that which one is legitimate and which one is not , because if you will make money in any project then you will say that , that project is better and guinine , regardless of the factor whether the project is legitimate or not .
So don't think any cryptourrency as a scam .
You need to see that how the project is working and at what condition is , I mean if any coin is launched at the exchange and market is better , but still actual coin is not made , then still we have better chances to make money by the fluctuating market , and in that case all depends upon us that how we are handling that market to make profit and loss with our trading strategy .
At the another side there are chances that even a real coin that is listed at the exchange get dumped badly ( by owner or any group of pump and dump ) then you will say that coin is scam only .
So all depends upon us and the result of the market of that Cryptourrency , nothing is sure .