Investment Model Interdependence Theory

2.3 The Investment Model
The investment model originates from the interdependence theory where the key concept is dependence. Sung and Campbell (2007, p. 100) state “Interdependence theory suggests that dependence is greater to the degree that a relationship provides positive outcomes (for example satisfaction) and to the degree that the outcomes available in alternative relationships are poor.” The investment model further expands the concept of the interdependence theory in two ways. First, the investment model states that satisfaction level, quality of alternatives and investment size are three bases for dependence, and secondly, the theory further asserts that these three bases for dependence produce what Sung and Campbell (2007, p. 100)

Sung and Campbell (2007, p. 101) also state, “Consumers’ psychological attachment to a brand will be stronger if a brand provides them symbolic values. That is, if brands provide superior benefits, which in turn result in satisfaction, consumers will commit themselves to establishing, developing and maintain relationships with such brands.” Thus, brands that provide the consumer with a high level of satisfaction will be purchased at a higher rate and would create a higher degree of commitment to the brand. Looking further into the quality of alternatives, in this case the quality and quantity of competing brands and the desirability and availability of their products. When alternatives are undesirable and limited, commitment is stronger. Consumers are more likely to commit to a brand due to perceived value and unique brand characteristics that the competing brands do not possess. Lastly, looking further into investment size, commitment increases by investing a lot into the relationship in terms of quantity but also in terms of the importance of the resources invested. In this case, investment does not solely include direct investments such as money, time, effort and personal identity, but it also includes “originally extraneous resources that become linked to relationship (for example shared memories or

With Coca Cola as an object of research, Sung and Campbell state that Coca Cola has a high availability making it possible for consumers to find the product almost anywhere with ease. The participants in Sung and Campbell’s study had parents who buy Coca Cola when grocery shopping, thus the participants constantly consumed the brand even though it was not necessarily intended. Sung and Campbell describe this consumer-brand relationship as an arranged marriage or kinship. They state (Sung and Campbell 2007, p. 109), "The relationship with Coca-Cola may be an involuntary union imposed by preferences of a third party (for example parents), but consumers nevertheless, intend to have long-term and exclusive commitment.” Furthermore, the participants had been drinking Coca Cola for 16 years on average, showing that they have invested a lot to the brand in terms of time, cost, habit and memory. The participants’ investment from childhood to their current age strengthens their commitment to the Coca Cola brand, because investments motivate the individual to persist and maintain the