I see only three fair reasons why you can exclude any coin from the listing of the exchange: 1) The developers of the coin stopped communicating with the support of an exchange and entire community of the project. It can talk about the scam. 2) Developers fail to follow the steps from the project roadmap, thereby damaging their reputation and questioning the validity of investments in the project. 3) Too low trading volume for a particular coin. In any other cases, I consider the delisting of any coin unreasonable and unfair to coin holders.
1 & 2 option isnt really that important but 3 which matter most with all exchangers out there. Volume is always been the primary reason
why a certain coin do last up into an exchange neither they had able to follow their roadmap or not as long theres an activity or its being
traded with high volume then they are still on the safe spot.Coin delisting is just a common clean up for those coins who dont have any more
use to the platform.