Mayfield said focusing on your brand is hard as a retailer because of the business of retail margins, seasonality and general economic cycle but Mayfield said that John Lewis was just one of a number of retailers to have recognised their brand as an opportunity.
He said: "The interaction retailers have with customers is so rich that there is an opportunity to establish a long term sustainable competitive position."
The John Lewis chairman pointed to the rebranding of the businesses department stores to John Lewis seven years ago, its investment of £100 million in store refurbishments and online as the platform the department store group had put in place which meant it was now in a position to exploit the John Lewis brand name via advertising.
Mayfield said: "It took us seven years to get to a place where we could talk to customers and give them a true picture of our business. Seven years ago, 12% of business was own label, it now represents 30%."
Mayfield added that the market had become "pretty tough, pretty quickly".
He said: "In a tough market the old stories are best. If you are a brand that knows its strength you can keep building on them. You have to understand your business and play the retail game your own way."
Mayfield said the business was committed to the policy of being never knowingly undersold. He said: "At the moment we are conducting trials to tighten it [the policy] up and implement it more vigorously which is a reflection of our commitment to that value proposition being a bedrock of the partnership."
He said the greatest challenge to the John Lewis business, which will double in size over the next 10 years, was to keep its culture. He added: "I’m confident we can do this. We have worked hard over the last decade and spent a lot of time focusing on the culture and behaviours we want to see within the business, so that as we grow we bring people into the business, who fully understand that.”
Mayfield said the record 20% bonus to John Lewis staff last week was an great example of John Lewis successfully exploiting what Mayfield called "the partner-customer profit circle".
He added: "I came away from announcing the bonus in Oxford Street [London] last week thinking that the market may be tough but John Lewis will be able to draw on 68,000 people who are totally pumped up and ready to trade."