This tectonic power shift toward consumers reflects the way people now make purchasing decisions. Once consumers make a decision to buy a product, they start with an initial consideration set of brands formed through product experience, recommendations, or awareness-building marketing. Those brands, and others, are actively evaluated as consumers gather product information from a variety of sources and decide which brand to purchase. Their postsales experience then informs their next purchasing decision. While word of mouth has different degrees of influence on consumers at each stage of this journey it’s the only factor that ranks among the three biggest consumer influencers at every step.
It’s also the most disruptive factor. Word of mouth can prompt a consumer to consider a brand or product in a way that incremental advertising spending simply cannot. It’s also not a one-hit wonder. The right messages resonate and expand within interested networks, affecting brand perceptions, purchase rates, and market share. The rise of online communities and communication has dramatically increased the potential for significant and far-reaching momentum effects. In the mobile-phone market, for example, we have observed that the pass-on rates for key positive and negative messages can increase a company’s market share by as much as 10 percent or reduce it by 20 percent over a two-year period, all other things being equal. This effect alone makes a case for more systematically investigating and managing word of mouth.