There are many reasons a tyre wears out prematurely. Some of the main reasons that commonly get misunderstood are
1. Underinflation - this is where the edges of the tyres wear out rather than an even wear across the tyre
2. Over inflation - this is where the centre of the tyre wear out rather than an even wear across the tyre
3. Wheel Alignment - the wheel alignment is the tracking of the wheels and if this not within the manufacturer's specifications it will cause irregular tyre wear