Of course, in practice, we can buy at a certain bottom. For example, before the stock price rises, it starts to pull back, and when it jumps, it supports at a certain support level and does not suppress it again. Then you can buy on dips at this time, indicating that this wave of stock price decline has begun to stabilize. At this time, it can often be said that the price is relatively low, and it can also be regarded as the bottom.
As for escaping from the top, I think it should be faster than bargain hunting. When the stock we bought keeps going up, but the technical indicators do go down, when the K-line closes, I think it should be out at this time. Even if it goes up later, don't feel sorry, because sometimes the top reversal is very fast, and a little greed may turn losses into profits.