Who Writes the Backlog?

The Product Owner has the final say in backlog prioritization. But who writes the backlog? Is it always the product owner?

My experience with Agile has been that, in the real world, the backlog contains two types of items:

1. The "user stories" that discuss functionality from the perspective of an end user
2. Technical stories--including things like technical debt, maintenance, package upgrades, etc. Things that don't represent user goals that the product owner would be focusing on.

Both types of items are important and need to be worked on. 

You can get into trouble in a couple ways:

1. Every item in the backlog is forced into a "user story" template ("As a...", "I want to...", "So that...").
2. The product owner is writing backlog items that are of the "technical story" variety since they think they need to write every story in the backlog.

If you have a product owner who has consistent time to write Jira tickets (or whatever issue tracker you have), you're pretty lucky. My experience with actually-existing-Agile is that the Product Owner is typically someone in middle management who is juggling multiple jobs, "product owner" of this product being one more job, and certainly does not have the time to dedicate to backlog management.

Occasionally you get an overactive product owner who tries to capture every task the development team is working on as backlog items, including purely technical tasks that are better written up by engineers or engineering managers/leads.

My opinion is that anyone on the team (engineers, QA, managers, product owner) should be empowered to write backlog items. When the nature of the backlog item is technical, let the technical people write it. When the backlog item is a "user story", the product owner should write the item, or at least delegate the requirements to whoever writes it (probably not an engineer).

Backlogs are just another tool in the tool chest of software engineering. As long as the people doing the work are clear on what the goal of the item is, and the acceptance criteria for its completion, then anyone can write them in whatever format they want.