When the bull run comes, we may feel like it's a trap, and many people keep waiting for the prices to dip a little so they can buy. However, it doesn't always happen, and they end up waiting indefinitely. Therefore, it's wise to take some calculated risks and start accumulating at the right time. Bull runs usually last for a considerable period, not just 2-4 days, so there is enough time to sell. However, if you become too greedy, anything can happen, so it's essential to set a target and book the profits. The key is to keep greed under control.
Maybe not having a specific target and selling right after it has reached, but one should always be careful as the market can always dip once it reaches the peak during the bull run, so, as you said, one should never get greedy in the cryptocurrency market because that will only cause them losses and if not losses, they will lose a part of their profits and then they start regretting why they sold so late, but again, if they sell early, they will still feel bad for not holding them a little more.
Basically, it's not possible for anyone to perfectly time the market, so the best thing is to sell when you think the profits you are getting are enough for you, and even if the price goes up from there, you won't feel bad because you have at least achieved what you have been aiming for and that is what matters.