Sometimes traders will go to the point that they think they waste the opportunity to gain more when some certain coins they hold pump more harder after they sell their coins. That's why on next time around they became greedy and turn loader when dump happens after all, that's why whatever the result is trader should think that profit still profit and they should really stick with the plan like the one you said since being consistent on doing that methods you mentioned can make a people a winner on their trades.
I suppose it resembles gambling a bit in that regard. When a gambler gambles and loses, they martingale, and when they lose again they go even harder on it, and they keep doing it over and over again until they win or they bust and leave with no money at all.
I have seen plenty of people who said they lost 10 times in a row at 50% win chance and how they claim it was a very low chance to reach 10 losses in a row at 50% chance, but the reality is that, 10th is still 50% chance to lose, it is not lower than the previous ones. So that logic of gamblers chasing losses do happen to traders, both when they lose money on a trade, or even on a trade where they made a bit but the price went super high so they missed on profit.
Those people end up being more "greedy" because they have seen what happened last time and they want to be in it this time but that doesn't mean it will be exactly the same.