It's interesting that you bring up this behavior! In my opinion, the reason people tend to buy at high prices is often driven by FOMO (Fear of Missing Out) and the desire to make quick profits. When the price of a coin is soaring, people often get caught up in the hype and believe that the upward trend will continue, leading them to buy at a high price.

On the other hand, when the price drops, people may become fearful and uncertain about the future of the coin, leading them to sell at a lower price. This can be especially true for those who are not well-versed in the market and the factors that influence cryptocurrency prices.

It's important to have a solid understanding of the market and the coins you are investing in, and to have a well thought-out investment strategy that takes into account both short-term and long-term market trends. It's also helpful to have patience and not to be swayed by short-term fluctuations in the market.