All due to the fact that in recent years, more and more fraudulent ICO, the teams of these projects sell their own tokens when they enter the exchange.
I am 100% agree with that.
All of "teams" (lot of times only 1-2 people behind the projects) sell their own tokens when they get listed on exchanges..
And the ICO investors react like this too so price go down and if you have "lucky" people will use this token for pump and dump..