Same mysql DB name and mysql User name

When I was reading documentations and help files to install ERPNext manually, I came across many documents. Most of the documents emphasized the

“mysql username and mysql db name must be same”.

What is the reason for that ?
For reference: Read step 3 of this link.

There is no technical reason why this must be true. It was a design decision, made by whichever person(s) wrote the Frappe Framework.

The configuration file 'site_config.json' allows for a 'db_name' key. And for a 'db_password' key.

But not a hypothetical 'db_user_name'

If the original author(s) notice your post, and decide to answer, then we’ll know “why.” :man_shrugging:

Thank you very much for clarifying. Hope original author(s) see the post.