Whenever you try to pick market tops and bottoms, you are making a prediction. Guessing what stock is going to outperform the market is forecasting, as is selling a stock for no apparent reason. Indeed, nearly all capital decisions made by most people are unconscious predictions.
Have a well-thought financial plan that is not dependent upon correctly guessing what will happen in the future.
History shows us that people are terrible about guessing what is going to happen - next week, next month, and especially next year.