Perceptions are neither the fifth nor the eighth P in marketing, rather they are the only P of any consequence in marketing.
Consider your seven Ps: product; place; price; promotion; people; process and physical evidence, all are subject to the power of perceptions.
Product: it is the perceptions around the product that count. No matter how good, novel or useful your product, if the prevailing perceptions say otherwise, it won't get past the starting line.
Place: it is the perceptions around availability that count. It may be in the store, but you can't find it! It may be represented in 500 outlets across the country but if that's not communicated and the audience perceives otherwise, it may as well be in none.
Price: it is in fact the perceptions around "value" that count. You could be more expensive than your competitors or cheaper by half, but if the price doesn't correlate with the value perceived by your audience, your product won't move.
Promotion: this is actually where you create, foster or shift perceptions or narrow perception gaps, via your communications. Your promotional activities create or degenerate perceptions around the brand.
People: your customers are moved to action or inaction by their perceptions. Your staff too will build or destroy perceptions around your product, for your customers.
Process: "The processes involved in delivering your products and services to the customer have an impact on the way in which your customers perceive you," says the UK's Chartered Institute of Marketing in its document: '10 Minute Marketing Mix'.
Physical Evidence: the perceptions of the physical environment in which the service is delivered.
What matters then, is not exclusively that you have all the elements of the marketing mix sorted out and in the right proportions, but most importantly that you manage the perceptions around these seven Ps.
Of course you're only managing perceptions when you're measuring perceptions. Measuring perceptions will inform your strategy in respect of managing the perceptions that exist around your seven Ps. It will tell you where you need to create awareness, shift or reinforce perceptions and close perception gaps.
