The curve a putt takes on its way to the hole as gravity pulls the rolling ball down whatever slope it crosses. Slope is the dominant force, but speed decides how much of it you see: the slower the ball rolls, the longer gravity works on it, which is why most of the break happens in the last few feet — and why a downhill breaker can bend three to four times more than the same putt hit uphill. Faster greens amplify break too, since the ball spends more of its journey at a crawl. Reading break is always a two-part answer, line and pace together: choose a firmer pace and you have chosen a straighter line, whether you meant to or not.