Less performance and more security. Lots of ameteur images use a secret file or inadvertently store a secret to a layer without realizing an rm or other proces

Less performance and more security. Lots of ameteur images use a secret file or inadvertently store a secret to a layer without realizing an rm or other process in another layer doesn't actually eliminate it. If the final step of your build squashes the filesystem flat again you can remove a lot of potentially exposed metadata and secrets stored in intermediate layers