Executives, especially at smaller organizations, sometimes doubt whether advertising is important to the success of their business. The same goes for public relations, marketing, and other promotional disciplines.
Usually, the suspicions crop up in the mind of the CEO or CFO, and usually after eyeballing the company financials. This is fine, up to a point. Their job is to maximize income while minimizing expenses. Advertising is costly, as a rule - and, in some instances, customer demand can make it totally unnecessary.