An up trend is higher pivot highs and higher pivot lows. But crack of any pivot low is not considered as trend change. Most traders consider the crack of a swing low leading to the highest high as trend change. Here the market in uptrend. A-B impulse move. B-C pull back. C-D impulse wave fail to exceed swing pivot B. Market falls Crack of pivot C is not counted as a trend change. Crack of A is a trend change as it is the swing low leading to the highest high pivot B. Pivot A is a MSP. Hope it is clear.