What is the purpose of frequent opening and closing of futures positions in one day? Is it market manipulation?

Frequent opening and closing of positions is a personal behavior with multiple purposes. As far as I know, there are intraday programmed trading, intraday short-term operation, personal habits and the purpose of brushing fees. If it is a customer with a large amount of funds, intraday trading may have the purpose of brushing the volume and K-line graphics during the day, which is suspected of manipulating the market.