Nature of complexity
Any product is a complex.
For example, an airplane is not only about transportation but also restaurants, shops, and mini movie theaters. Even if we eliminates the mentioned “extra” services, logistic is also a must-have functionality of an airplane. The possibility of the combination of the two further complicates what an airplane should be.
For another example, even a chair is a complex. We need a chair to be a table in situations like when we seat on the floor plus there is no mini tables around. Or, we want a chair to be a simple fitness facility to provide stable height difference.
Thus, we see all the products play different roles in different contexts. We might think the essence of a product means users’ highest frequency of use on that aspect. However, it could often be not the case. For instance, one of the one sentence intro of a smartphone is a portable internet communication device, but the function users use the most by smartphone is camera.
Human form of life consists of complicated contexts, so all products are complicated in nature.
Critical insights of a product, not the essence of a product
As a result, there should never exist one sentence intro to tell the essence of a product. Nevertheless, to tell critical insights of a product for trade-off between features, prioritizing resource allocations and marketing, one sentence intros can definite do it.
In conclusion, product design is not about design the product according to its essence. In opposite, any product design is a process considering complicated human life contexts and than outputting a resource/economic efficient mechanism to handle those distinct scenarios. No one sentence essences, but one sentence insights can help a lot.