“Don’t create a sitemap manually like that,” Google’s John Mueller said.

Instead of creating the sitemap manually, it is recommended to do perform the below:

– Generating the sitemap from the CMS or the underlying database directly.”
– Getting a sitemap from the API where the devlopment team originally pulled the list of URLs would also work

Why is this better than manually creating a sitemap?

That is because when creating a sitemap for a large site, or any site, you have to consider not only how it will be created but how it will be kept up to date.

For example, a site with tons of product catalogs could be adding and removing tens of thousands of products every day.
It would be almost impossible to manually maintain an updated sitemap like that quickly. Manually creating a sitemap is not a realistic solution when automated options exist.

So do remember to keep you sitemap updated automatically and frequently especially when you have changes in your website.