I'm reading a few automated scripts written at work, and I'm seeing either yum clean all or yum clean metadata after creating a .repo file in /etc/yum.repos.d for a new repository. Now, I'm automating something for which I'll have to add a new repo file and I'm wondering if this does something other than cleaning the cache and if I should add it, but I don't want to add anything without really understanding what it does.
EDIT: It's suggested even here in this answer: https://superuser.com/a/504109/5184