How justified is the creation of a large number of layers when writing a Dockerfile?

Creating a large number of layers in a Dockerfile is not always justified. Each layer increases the size of the final image and can complicate caching and building. It is recommended to combine commands that are logically related to reduce the number of layers and optimize the image size.

For example, instead of:

RUN apt-get update
RUN apt-get install -y curl

It is better to write:

RUN apt-get update && apt-get install -y curl

Thus, the balance between readability and image size optimization is a key factor when designing a Dockerfile.