Why is Backup not integrated into WordPress?

I have spent a while looking at backup solutions, and I am just confused.

There seems to be 12 pages or so of plugins when you search for backup, and they all seem to do different things.

What I don’t understand is why it has to be that difficult. Shouldn’t a thorough and complete backup of the database and the website files be an INTEGRATED function in WordPress? It’s one of the most obvious and critical aspects of having a site – having a solid backup.

If anyone can help me with a simple free solution for backup, I would be extremely grateful.