Set a bucket's default owner
Skill matching handles most assignment, but every bucket can also have a default owner for events where nobody on the team has the skill.
What a default owner does
A bucket's default primary owner gets its tasks when nobody on that event has the matching skill: "Dana always runs Marketing". If you also set a default secondary owner, they're added to every task in that bucket as the backup.
Setting one
Go to Settings → Task buckets. The table shows each bucket's default primary and secondary owner, its open and total tasks, and how many events use it. Edit a bucket to pick its owners. You can also set them while creating an event, on the wizard's Team step, where owners and admins can save their picks as the new default.
When it kicks in
Third in line, not first. The app tries a skill match first, then a workload tie-break among matches. The default owner is used only when nobody on the event has the skill, and the organization owner is the last resort after that. If tasks keep landing on the default owner, someone on that event is probably missing the skill.