Define Your Own Job
The closing contrasts are about self-management. Good product managers define their job and their success. They don't wait for a manager to hand them a charter. Bad PMs want to be told what to do, which is fatal in a role whose entire point is deciding what should be done.
And the last line, almost a throwaway, isn't one: good PMs send their status reports in on time every week, because they are disciplined. Bad PMs forget, because they don't value discipline.
It reads like a small thing after 'CEO of the product.' That's the point. The CEO frame isn't a swagger statement, it's a discipline statement. Responsibility shows up in the unglamorous weekly mechanics or it doesn't exist.
“Good product managers send their status reports in on time every week, because they are disciplined. Bad product managers forget to send in their status reports on time, because they don't value discipline.”
Key idea
Nobody hands a good PM their charter. They define the job, define success, and back it with boring weekly discipline.