What's An End Grain Cutting Board? This is probably one of the biggest questions I have to answer. Wood, by nature, is a series of fibers all locked together. Most woodworking applications start with people shaving fibers length wise. This is how wood is able to be whittled and shaven off using hand tools. The hardest thing to do with wood is cutting into these grains. What makes this so difficult is that the fibers which are usually parallel with your blade are now perpendicular. With this change in orientation, blades and cutting tools have to sever several thousands of fibers at a time.
Like a Hand tool for woodworking; cutting across the grain dulls your knives faster or can even damage your blades.
By repositioning the end grain facing up your knife blade is allowed to penitrate in between the fibers and therefore prolong the life of your knives.