To begin with, who can actually achieve that? If you are investing your money in bitcoin, the most likely reason for this to be the case is that you want to increase your capital and protect yourself from inflation, but at some point you may want to use part of that wealth for yourself, so never selling is a goal that is difficult to achieve, a better goal is to set the time you want to hold your coins, and once that time passes you can start to think about what will be the best use for that wealth, which could include to keep holding your coins as you do not need them right now.