Garbage projects are really polluting the cryptoworld and staining its image especially if these projects are just scams. Some projects could not make it reach its target capital during the crowdfunding which can also be the reason for the project to stop.
I think that with numbers that we see during an ICO, a real project can survive for years.
The real problem is that many projects are created to scam people and not issue anything.
In 2017, there were a lot of fraudulent projects, but you could also make good money on them, because there was a cryptocurrency HYIP, and now even excellent projects cannot collect a cap.