personalize the brand for the consumer and create the relationship between the consumer and the brand. To ensure endorsement is successful, the celebrity should match the brand and the consumer. The effect of using a celebrity endorser that consumers look up to and want to emulate can lead to increased congruence between the values of the consumers and the brand, and improve the relationship between the two. Industrial markets In industrial markets, organizations regard "heavy users" as "major accounts" to be handled by senior sales personnel and even managers; whereas "light users" may be handled by the general sales force or by a dealer. Portfolios of brands Andrew Ehrenberg, then of the London Business School said that consumers buy "portfolios of brands." They switch regularly between brands, often because they simply want a change. Thus, "brand penetration" or "brand share" reflects only a statistical chance that customers will buy that brand next time as part of a portfolio of brands they prefer. It does not guarantee that they will stay loyal. Influencing the statistical probabilities facing a consumer choosing from a portfolio of preferred brands, which is required in this context, is a very different role for a brand manager; compared with the much simpler one, traditionally described, of recruiting and holding dedicated customers. The concept also emphasizes the need for managing continuity. Issues After brands are well established and have a decent flow of consumers, problems may arise such as slips in product quality or in safety of products, or lack of customer care. Such problems can be detrimental to a brand that has become too confident. Many brands continue to get away with scandals, and it does not affect their image in any way. For example, the Coca-Cola brand scandals including murders in Colombia, crimes in India, and various health dangers; all of which relate back to the company name. Yet the power of the Coca-Cola brand puts it at the top of its field. The reputation of such a massive organization is hard to dent with the powerful distribution rights and funds to create some of the best ad campaigns. Stability Many markets exhibit overall stability, or "marketing inertia." In their essential characteristics they change very slowly, over decades or even centuries rather than over months. This stability has two implications: The first is that those who are brand leaders are especially well placed in relation to