I have learnt never to sell my Bitcoin with the hope of buying it back when price supposedly reduces. There is a high chance you will never replenish the Bitcoin. So I feel this pattern of buying at the dip and selling at the peak will not work for everyone as not everyone have the discipline to do that. Besides, is there any way to completely determine what the dip and peak are?
Assuming you bought Bitcoin around $8k and some around $15k, probably you bought lets say 5 BTC in total. If you sold this in 2021 around $60k, this represent a descent profits. fast forward to today, there are high chances you have not replenished your portfolio with 5 BTC and this means even if you might have more money in fiat, yu have depleted your Bitcoin portfolio and anything that makes Bitcoin create a new ATH, you might likely be depressed seeing that your overall decision was not the best. On the other hand, you have kept a large chunk of that money as fiat, there is the possibility you inflation would have eaten deep into the money.
The ultimate aim of every believer in Bitcoin will be to own Bitcoin. In other words, you can not be a true Bitcoiner when you are overly ready to deplete your portfolio at the sight of profit even though you have the intention of buying it again at some point as this have turned to a game of probability. It is not a good position to be in my opinion.
Your overall theme sounds good, but there is something wrong with your example.. because if someone bought 5 BTC for an average price of around $12k, that person would have spent around $60k for those 5 BTC, so there surely could be ways to sell some of the BTC and buy them back and to end up with more BTC. So you are seeming to give away too much by assuming that they are able to sell at or near the top.. and if anyone ends up selling at or near the top, they end up having a lot of options to buy back lower if they did not end up spending it for consumption purposes and they kept that money in their investment portfolio.
I understand your point completely and yes, you are right. Nevertheless, what I gave was an assumption... from experience, those who buy low to sell high usually do not necessarily wait for the peak but do sell as soon as they see considerable profits. So, I doubt they could be so patient and organized to buy at $12k and sell at $60k. The chances of this happening is very slim because no one would be able to know for certain that Bitcoin will go as high as $60k before the present retracing.
Looking at historic data and considering that market have this way of testing our psychology, it is most likely that they bought and sold at prices we are not even capturing. To be specific, Bitcoin made a high of $19,891 in 2017 before retracing to around $3,200 in January 2019. It rallied to around $12k in April 2019, so anyone who bought low would have targeted the previous ATH of 2017. This means those that bought around $12k would have sold around December 2020 when Bitcoin smashed the high of 2017 to hit around $29k before 2020 ended. From this point onward, Bitcoin never experienced any huge dip and this means that those who buy low to sell high might have missed the bull run of 2021 and even if they managed to jump in after selling their previous stash for profits, they most likely bought above $29k.
The point I am making is that even though this patter appear attractive to some people, it might make someone miss wonderful opportunity such as buying around $3200 and riding the wave of 2021. This kinds of HODL is only possible for long term holders and not those with the mindset of buy low and sell high.... the high might not really be the true high.