Not everything thing that is useful is a product. In the same vein, not every feature belongs to a product, even if it is useful.
This understanding is important to help us spot what a product is.
A product is different from a collection of useful features.
A product starts with a problem to solve.
Then an opinion on how to solve that.
Then a set of principles as to how to solve the problem.
Forming a cohesive whole to a well-defined customer or user.