https://support.atlassian.com/jira-software-cloud/docs/use-your-scrum-backlog/

The last bullet point in the "About the Scrum Backlog" section says:

"there's at least a status being mapped to the right-most column.
For example, if you have the columns To Do, In Progress, and Done, ensure that you have a status mapped to In Progress at least. If you map all the statuses to the first (To Do) column, you won't see any issues in the Scrum backlog."

The first sentence talks about the right-most column ("done" column) but then the example talks about mapping a status to the "In Progress" column.

Is the example incorrect or am I just not understanding it?