Two-timing is usually poor behavior but that is actually an important rule for stocks you hold. One is the stock market trend, which can change any day, and the other time to be on alert comes around every three months, in the form of earnings reports.

Earnings surprises can be good and bad, and they can make stocks reverse course — sometimes dramatically. Even top growth names are not immune to earnings surprises — or even shocks. Therefore, holding stocks through earnings can be risky, although there are some workaround strategies.