It is problematic for a person to believe that he can sell bitcoin and buy back cheaper rather than just accumulating bitcoin on a regular basis through buying only.
The thing there is those guys who believe that they can sell their bitcoin investment and buy back cheap are just funny guys who still lack knowledge and understanding about bitcoin investment, because bitcoin investment doesn't work that way. It Will be better they keep accumulating bitcoin on a regular basis through buy only and hold than even thinking of selling to buy back cheap. selling their bitcoin investment to buy back cheap is just another Risk on it own, why because bitcoin may end up not dipping to the extend they are expecting it to dip in other for them to buy back cheap, which they will still end up buying back bitcoin at a higher price and still end up regretting why they even sold their bitcoin investment in the first place.
One thing about bitcoin is the uncertainty in price timing capped as volatility. A person may decide to sell off his bitcoin ignorantly hoping to buy back at a certain price, which may not be completely impossible. But the timing is not easily known as bitcoin is self driven and volatile at its own pace. So holding up your bitcoin remains all that anybody can do because instead of spending sleepless nights reading charts, making assumptions, waiting for dips you know not the time it's coming, then leaving your bitcoin without selling will definitely remain the best option.
Some people believe that wars usually affect bitcoin price during the period and as such, sells their bitcoin stash whenever there's a war among the world powers, butit's not still a guarantee that it would work that way.