The best time to enter and exit the market is not the lowest or highest point, but the following two sentences:

Limited decline, large potential for rise, large profit - enter the market (even if the market falls at this point, it will eventually rise to a higher point and there is enough profit space)

Limited rise, large space for decline, high risk - exit the market (even if the market rises at this point, it will eventually fall to a lower point and there will be a cheaper price)