I'm afraid that they don't really last long because they can't afford to hype their coins forever without updating and constantly developing their platforms in order to catch up with the new trends concerning their competitors' offers to their investors. Also, they don't have any partnerships that could make their platforms last longer like DogeCoin. In other words, when you invest in such kinds of projects you better know they are not recommended for the long term and you need to know when to pull them when the price starts slowly decreasing in the crypto market.