Often, it's tempting to begin creating or improving designs by jumping in and moving the elements of the design around, adding something here or there, to try to address customer concerns.
However, experienced product designers know that surface treatments like this often do not address the real problems people have with using a design. We have to look deeper to make sure the whole concept behind the design makes sense for the people and the environments of use.
When you talk about looking under the surface, it generally means that you are looking at the model of interaction that underlies the actual appearance. Sometimes, there is a mismatch between the design concept and the conceptual model that users and customers have.
That's why it is useful and instructive to create a conceptual model of the product or process, to make sure the assumptions used in the design are correct. Conceptual models are meant to represent the blocks of functionality or process steps that people move through regardless of the design. They are representative, and therefore, they don't look like the actual final product.
This example shows the main steps of driving to a destination, which helped me brainstorm innovative solutions based on a solid conceptual foundation.