There are so many indicators that could tell you if a coin is good or not. For most parts people check on how much cap the coin has, the movements it has shown over a period of time and if its developers are active to keep on supporting the coin like regular pumps and all that. However, it doesn't ensure that such coin would really prosper because one of the most important elements in this market is the support of the community. Unfortunately, if it will not get enough traction to gain value, then like any other coins, it would be doomed to die out. One thing to check as well is how the market and the community sees and supports it, if it gets a lot of good feedback, then that could be a good sign.