When a cupcake becomes a wedding cake`, Intercom's approach to building product emphasizes "think big, start small" and the "cupcake approach". This involves breaking down ambitious projects into smaller, iterative steps, delivering value early to customers, and gathering feedback to inform future development. While this approach can be challenging to implement, it allows for faster iteration and better understanding of customer needs. However, it's easy to fall into the trap of adding too many features to a project, which can lead to complexity and difficulty in validating the approach. To avoid this, Intercom advises keeping scope tight and releasing "cupcakes" that are small but meaningful, rather than trying to build a complete product at once. This approach requires discipline and careful planning, but can lead to more successful and customer-focused products.