This two-way sync is what keeps a contact's board seats visible without anyone having to enter the same information twice.
What happens when you add a board member
When you add a contact to a company's Board block on the Org Chart:
That company is added to the contact's profile as one of their companies.
The job title associated with that company on the contact's profile is set to Board Member.
Example: Priya Menon is a contact whose primary company is Acme Ventures, where she is VP of Talent. You add her to the Board block on Meridian Robotics' Org Chart. Her contact profile now shows two companies: Acme Ventures (VP of Talent, primary) and Meridian Robotics (Board Member, secondary). Nothing about her Acme Ventures record changes.
What happens when you remove a board member
Removing a contact from a company's Board block removes that company from their Contact profile. Any other companies on their profile, including their primary company, are not affected.
What happens if you remove the company from the contact's profile directly
This sync runs in both directions. If you remove the board-member company from the contact's profile instead of from the Org Chart, the contact is removed from that company's Board block as well.
What happens if the Company profile is deleted
If the Company profile a contact is a board member of is deleted, the board membership is removed from the contact's profile along with it. This follows the same behavior as any other company association on a contact profile.
What this does not affect
A contact's primary company and title are never changed by adding or removing board memberships.
Board membership does not create a reporting-line relationship. A board member added this way will not appear connected by a line to anyone in the main Org Chart hierarchy.
Existing "Reports To" relationships on the contact are untouched.