High volume in late trading usually means that a stock has a large number of buy orders near the close, causing a sudden rise in the stock price. This situation may be caused by a variety of factors:

1. The main force attracts funds. In order to collect more chips, the main force may increase the stock price in late trading in order to buy at a lower price.

2. Whitewash the K-line chart. The main force may increase the stock price in late trading to repair or improve the K-line chart pattern and create the illusion of rising prices.

3. Major good news. If a stock is about to announce major good news, it may attract a large number of investors to buy in late trading, causing the stock price to rise.

4. Shipping. After the stock price rises for a period, the main force may increase the stock price in late trading in order to ship to other investors at a higher price.

5. Protect the market. When the stock market is unstable or the market falls, the main force may increase the stock price in late trading to stabilize the market or reduce losses.

6. In general, large-volume increases in late trading may be a strategy of the main traders, and their true intentions need to be comprehensively analyzed in conjunction with market conditions, news and other factors. Investors should be cautious when encountering this situation, conduct in-depth analysis of the market, and master certain trading skills.