Currently on the coinmarketcap site only about 1590 projects compared to at times more than 1700 projects. They have left many projects without developers or scam projects. I personally invested in some of these projects and lost a lot of money like bitconect and centra. Do you trust the projects you are investing in and will keep them for a long time until they succeed or are they just looking for profit in the short term?
every project has their roadmap. you can see it then you can take a conclusion about that project
the best thing to do, just take it for short term. bcs in long term it's so risky