Function

Function is what a product or service is intended to do — the job it is meant to perform for the customer — and how well it performs that purpose. This includes reliability, meaning it works consistently, and effectiveness, meaning it actually achieves the result the customer needs.

Take a rechargeable power bank. Its function is to charge a phone when you are away from a plug. A good one holds enough charge for several top-ups, charges at a sensible speed, works with your cable and does not overheat. If it cuts out or charges very slowly, it is unreliable and ineffective, even if it looks attractive.

Why function matters

Products that perform their function reliably and effectively are more likely to satisfy customers. Satisfied customers may return to the business, recommend it to others and leave positive reviews, which can support sales and reputation. A product that keeps failing can lead to complaints, returns and lost trust.

Prioritising function suits customers who value performance and reliability more than appearance or a low price. For example, someone who needs a power bank for a long journey may pay more for one that works every time rather than choose a cheaper model that may let them down. Function can therefore be a reason why a customer picks one product over another.