Never ever hesitate to take profits, even if the project is the best ever, take profits, invest again when price is down because believe me, the price will surely go down
It is because of greed why most of us forget to take profits. And I think every newbie experience that and it taught them a lesson during those times.
Every investor should set their achievable profit. I think this is the mistake because we often set our expectations so high that it is impossible to happen.