Why is the oval office round?

In 1909, William Howard Taft had The West Wing expanded and extensively remodeled. He relocated the chief executive's office in the middle of the south side-taking over the secretary's round-ended office-and changed its shape to a full oval

For President Taft, an oval office may have symbolized his view of the modern-day president. Taft intended to be the center of his administration, and by creating the Oval Office in the center of the West Wing, he was more involved with the day-to-day operation of his presidency than were his recent predecessors.