They are investors with weak hands and unstable emotions. Typically, these are new traders or investors who fear losses. It can be assured that this is one of the strategic mistakes in trading that makes them too afraid and lack confidence in the coins they buy.
Bitcoin has strong fundamentals, and this coin even has high liquidity. There are many instances of dumps and pumps, as well as bearish and bullish markets. These are elements that cannot be avoided, so if one cannot capitalize on market conditions effectively, a trader will prefer the safer route of selling their Bitcoin, while they don't know that the price will definitely bounce back; it's just a matter of time.