All airlines are the same. They fly the same planes to the same airports for (roughly) the same prices. What differentiates them? Attention to detail. It’s not just the functional detail – it’s the experiential detail that really makes the difference.
It’s the same with software. If the application you are building was an airline, which airline would it be? All to often developers focus on the plane, building something to fulfil the utility of getting people from A to B. Yet the customer doesn’t care about whether it’s an Airbus A330 or a Boeing 777, what they care about, and what they remember is the experience they have.
(This can be a useful exercise at the outset of a new project, ask stakeholders to imagine their finished applciation was an airline, what brand would it be? This helps anchor expectations; are you building a full service Singapore Airlines or a no-frills EasyJet?)