This part is true... it can take several years to start to get into profits, yet even the mere fact that you are in profits would not even necessarily start to mean that you need to sell any coins. .
My point exactly. Most short term investors have a fixed investment duration, and then they sell off their coins, which as you've stated isn't the best. And as it takes several years to start making PROFITS, they mostly do not take heed to that, and their investment duration falls below the 'several' years that they need to get into profits. Bitcoin being as unpredictable as it is, can drop or whatever other reason, they find themselves incurring significant losses.