While seasoned goodyear welted shoe users know this, a lot of first-time users of this construction have a few questions usually about the concept of breaking into your shoes. Mostly the why and the how.
The Why- The materials used to make the shoes, vegetable tanned insoles, outsoles, the welt, cork and some upper leathers all tend to be a bit stiff to start off with. This is simply down to the nature of the material and perhaps it has been made and sitting in storage over some time. From the time the leather bends was made in a tannery, to being made into a pair of shoes and then perhaps lying in a shoe box for a few months, can be anywhere from 4 months to a year or more. This makes the leathers a bit stiff while it is waiting to be used or ‘broken-into’.
The How- It is recommended not to wear your new pair of good year welted shoes for a long time the first time you wear them. The very first wear can be around the house for up to an hour. The next day a couple of hours and step out with it. This will help roughen the sole bottom if it is a leather sole. Then give it a break for a day and perhaps wear it the next time for half the day. By the end of it, you should now be starting to soften the insole and outsole but the upper might still be a bit stiff depending on the type of leather. Suedes will be soft from the first wear, but box calf type leathers soften with body temperature and sweat over extended periods of wear.
It is said that about 10 hours of wear is what it takes to break into a shoe. This is very subjective as it depends on the materials, the environment of use, the weight of the user and other variables. But this should give you a ballpark figure.
Once you have broken in, the insole will have an impression of your foot which will deepen with time and darken in colour due to the character of vegetable tanned leather. The cork below it will also start to mould to your feet and by now hopefully they are starting to feel comfortable!
Also, remember to rotate your shoes and not wear the same pair every day. This gives the shoe, time to breathe and restore itself, hopefully in a good shoetree. Of course, it also elongates the life of the shoes.