Screenshot: The 'Components' screen
You can optionally set a Default Assignee for a component. This will override the project's default assignee, for issues in that component.
If an issue has multiple components, and the default assignees of components clash, the assignee will be set to the default assignee of the component that is first alphabetically.
Default Assignee Option
Issues matching this component will have the assignee set to the same default assignee as the parent project.
The assignee will be set to the project leader.
If the project leader is not permitted to be assigned to issues in the permission scheme this option will be disabled and will say "Project Lead is not allowed to be assigned issues".
The assignee will be set to the component leader.
If the component leader is not permitted to be assigned to issues in the permission scheme this option will be disabled and will say "Component Lead is not allowed to be assigned issues". The Component Lead option will also not be available if the component does not have a lead assigned to the component. Instead under this option it will say "Component does not have a lead.".
The assignee of the issue will not be set on the creation of this issue.
This option will only be available if "Allow unassigned issues" is enabled in the General Configuration.