The chemicals used in tanning the leather, only preserve the usefulness of the skin for a certain period of time. Nature is no longer able to do what it once did. 
The responsibility now becomes that of the "new owner."
Regular cleaning and replenishment of natural oils will keep the leather in good condition for a very long time. Oils in the leather will dry out and evaporate even when the leather is not regularly used. To keep the leather soft and flexible, dirt and grime which have accumulated on the surface must be removed and the oils be periodically replaced, usually about once every year. Our leather technicians can bring your leather back to its original condition.