This is true. Why you will sell your coin if you know that it will make you loss your money. Instead you can just hodl it until the right time, until the market will rise or be in a green row again. Unless you really need money to sold it. So think wisely.
I think if you want to produce, wise and be smart. create a couple of research and get some success. do not only hodl if you think you lose some. always check the market if holding you have the opportunity to bounce back. if you feel lost large and still down just thinking minutes then sell, find the other.