A new starter in any martial art loathes wearing a new-looking suit
because its new appearance echoes their own inexperience.
They seek to make the outfit look worn-in and used.
If an instructor wore a new uniform, the uniform would look fine.
It's not the uniform that is the issue, it's the individual.
An instructor carries themselves in a particular way - irrespective of attire -
and a new starter can't emulate this.