It usually surprise me when I see investors complaining about a good project that didn't increase or providing returns immediately it got listed on the exchange and they term it scam or say different things like rekted.
But the truth is, are these investors investing in the project because they believe in it or are they just in it for the immediate profit and move on? Because if you are investing in a project because you believe in it then you should be willing to HODL the tokens and wait for the team to gradually deliver the project and meet its necessary roadmap before you judge it and not condemn it on its first listing.
Believe me, most investors would like to hold their coins for a long time, but the market of cryptocurrencies can move so quickly that it is impossible to do so especially when we are talking about new coins, you are ignoring how quickly a coin can lose its value, and as such investors have no other option but to act as quickly in the event that a coin in which they are invested begins to crash.
So I do not agree with you, investors have to move as fast as they can when a good coin begins to go down in value and if that means that some coins do not achieve the potential that they could reach then so be it, an investor is not putting his money at risk just because he believes in a project he wants to profit from it and if he cannot do that he is in all his right to sell his coins as soon as he can.