Some are projects that have a changing variable over a long period of time (Framingham Heart Study, E. coli long-term evolution experiment) or strive to exist a long time (Clock of the Long Now). I would argue that these projects -- their process, data collection methods, and goals -- may have been developed quickly, in a short amount of time. Their longevity is proof that the original project was well established. But the same could be said of the invention of the wheel, shoe, sliced bread, etc