If the coin has good developers and they are following the roadmap then most likely they would be able to push through the project and achieve their goals which would result for the existence of the project for a long time given that their project would be useful. Unfortunately, we can only see a little percentage of those coins that has these types of persistence because some just give up easily that's why the value of their coins just continue to go down.
Even though bitcoin is what they call has ancient kind of technology already because it is the first one, it is still the most famous and valuable one because it has the demand of the people. It would still exist for a long time and may not be gone at all and retain its position if there is a catalyst that would catch investor's eye and it will continue to soar high.