To favor composition over inheritance is a design principle that gives the design higher flexibility, as you can choose which domain-specific objects should be incorporated into your ultimate object. It's like arming your base machine with tooling, dedicated to running a specific task, but not building a wide hierarchy structure of classes covering all possible hardware combinations.

In fact, with the composition approach you can more easily respond to the requirement changes regarding classes, as it does not require deep dependency investigations which you would spot while implementing code with the inheritance approach.

On the other hand, there is a clear drawback: composition transfers additional responsibilities to the developer. The developer should assure that all component classes that are used to build the composite should implement the methods named in the same manner to provide a common interface.

In the case of inheritance, if the developer forgets to implement a specific method, the inherited method with the same name will be called. Additionally, in the case of inheritance, the developer has to re-implement only the specific methods, not all of them, to gain a common interface.