We are witnessing a reflex rally in the context of a larger correction after 2 years of bull move from 2009 onward . Most bear markets have several hope and disappointment cycle. You get stretch of time where markets corrects followed by relief rallies followed by drops to new lows.
The volatile up down cycle results in rinse and repeat. That tends to be bear market pattern.
As of now the rally still has more upside and probably last for few weeks. If leadership expands to small caps and new companies then that will lead to big move. Absent that we will have another failure. One of the big problem is complete absence of new leaders. Same old tired leader continue to attract buyers. Which puts longevity of rally attempt in question.