A strong core is essential for success. This is true for brands as much as it is for physical fitness. An increasing number of people in your local gym are trying to improve their ‘core strength’ by working out the muscles deep in the abs and back that help keep the body stable and balanced.
In the same way, a strong core is also important for keeping a business healthy and in shape. Indeed, most successful businesses are built on a solid foundation of a core business where they have a leading position. Timberland might sell a range of clothing and accessories, but the original Timberland boot is still crucial from both a business and brand image standpoint. The same goes for Dove and its little white cleansing bar and Hellmann's with its original mayonnaise. Growing the core has many advantages. By selling more of the stuff you already do well, you grow without adding complexity. Instead, you make what is strong even stronger, both in terms of brand equity and economies of scale.
However, despite the advantages of growing the core, companies that successfully do this are in the minority. Research shows that many companies neglect their core business and, in doing so, miss out on opportunities for profitable growth (1). Instead, they over-rely on stretching away from their core with new products or services. Like the favourite elder child, brand stretch gets all the love and attention. Now, brand stretch can drive growth, as shown in my earlier book, Brand Stretch ...