What this means? Why they do that? Is everything just done by exchanges or project itself,
I believe that it is a collaborative event between the exchange and the project, the project will be trying to make sure that they meet up to coinmarketcap cap requirements
They thereby creating a fake volume by collaborating with the exchange and perhaps to draw the attention of investors to buy their token , lots of new exchange are guilty of this, and it doesn't speak good for cryptocurrency market generally