Originally Posted by MohammedC
Statistically thats when the ball is scruffy and dry to one side. But you can prolong it by looking after it. I remember England used to designate one player to keep shining the ball.
I also noticed during BD bowling the ball looked the same on both sides. Yes, England I saw was meticulous holding the ball by the seams only with two fingers and treating it with such care. BD I did not see that care.