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.
Theres are two type of investors long term and short term those investors who complain in a project that not increase is surely short term investor that want to earn profit in a short term.
A true investors are willing to hold for long term even the price dump so hard because they believe in a project no matter what happen just like bitcoin its take 8years to get their all time high.
but it doesnt mean you must hold all of your coin until 8 years. there are many type of investor like what you said before. and sometime i use all method depend on how good they are or how i think to not believe that they can be good in a future. and mostly i keep it until some month or until it can be sold.
investor complain cause they are tricked, and have many bad experience.