The reason they are doing so is because they just want to develop the project and get more and faster profits. That's why they waste more time on something they will do and earn.
well, cryptocurrency for the others is like a business they create a new coin, and if it's good then it have a chance to be a popular and one of the trusted coins. so the founder or owner of that coin will earn big. but if it failed just a small amount of their money is loss because their coins is failed. but now, too many coins amd I am sure that the pther just wasting their time