I haven't read similar articles, but from my experience and what I know, the high-frequency trading in financial markets you mentioned should not include the China stock market, but refer to other types of financial derivatives trading, such as futures and options.

Because these financial derivatives transactions mentioned later can be done in both directions, that is, they can be long or short. If the winning rate of each transaction can reach 5 1%, then the probability of failure is 49%. If you can control your position, you can think of winning and losing rates as probabilities. Different positions will bring different expectations.

It is precisely because their probability difference is 2% that they can achieve the so-called intraday profit in a certain number of transactions.

But I must point out that this statement should be premised or idealized (if it is not mentioned in the article you read, it is best not to read such an article), because every transaction will have its transaction costs, and high-frequency trading itself brings higher costs. If these costs are put aside, it is not advisable to calculate the idealized profit probability with realistic probability.

Of course, it must also be admitted that the real meaning of this view is that if every transaction has a win and a loss, then you only need to put most of your many transactions, or the profit is greater than the loss, then the transaction as a whole is profitable.