One thing that can make leather soles wear down a bit extra fast is if there is gravel that get stuck on them, and then create holes. However, one can easily reduce the risk for this.

 

Although leather soles are hard and durable, especially finer oak bark tanned variants, they are of course worn down over time, and depending on the stresses they are subject to, life expectancy varies. One thing that you may not always think of but which do creates some extra wear is when small pieces of gravel get caught in the leather. They can get stuck quite hard and sit for a good while, digging unnecessarily deep pits in the sole.

This picture and the above are examples of where you can see how grit is stuck in the leather sole, and the deeper pits sometimes come from those who were sitting stuck for a while. Pictures: Reddit

To minimize this, you can do two simple things. First, always have the habit, even if it’s dry outside (the risk of bigger gravel getting stuck hard is higher when it’s wet outside, but often happens even in dry conditions too), rubbing the shoes properly when you step in on the doormat at home, at the office, in stores etc , then most of them come loose. Then it is also good that when you get home, and you (as you should have learned by now) brushes/wipes off the shoes and puts in the shoe trees, you also take a quick look under the sole and see if there are grains of gravel that are set take a bit extra hard, which you can remove with your finger nails or similar. Grits that sit tight can also happen on rubber soles, so do not hurt to take a look at them too. Simple means for a bit better durability.