That is exactly how it is suppose to be, holding for a long period of time before having a thought of selling but it appears that some people have made up their mind to buy and sell whenever there is a little profit and hoping to buy back when the price drop although it may look like a strategy for them but trust me it is not the best approach to Bitcoin investment and most of these people don't use what they can afford to let go that is why when they buy at a certain price they will have a target where they want the price to reach before they will sell and whenever this doesn't go as planned and they used what they can not afford to let, they will sell even in loss and this means that you are going backward instead of forward.
Those set of people that always have a mindset of selling their Bitcoin anytime when they see some little profits in Bitcoin I always consider that type of people as traders. To my understanding, they are not investors. If someone can't hold Bitcoin for certain years before thinking of selling, they are traders pretending to be investors, and this kind of people hardly make it from Bitcoin.
Having a mindset to sell when the price of Bitcoin rises and buying back when it falls this method has made some people lose more opportunities because the price of Bitcoin may not fall to the target they set.
As you said, the best approach to Bitcoin is investing in it, not trading it. In fact, trading exhausts much of people’s time, time which could be used for other hustles that could bring in more money to continue accumulating Bitcoin.