Natural wear and tear
To ensure that you have a good grip on the ball, there must be friction between the ball and your glove. This is a similar principle to cars or bikes that brake on the road. In both cases, friction can lead to abrasion.
As a very rough rule: the better the grip, the shorter the lifespan of the glove. (See graphic)
The higher the grip of the glove, the softer the foam. To return to the tyre example: in Formula 1, tyres can enter a bend at 250 km/h, but won't last for 50,000 km.
The same principle applies to our professional foam. The grip is extremely strong, which reduces the durability of the glove slightly.
Normal abrasion and how to reduce it