The quote beneath doesn't explain why the wheel in the navigating bridge wasn't the main one. If the bridge's wheel suffices for 'frequent changes of course or maneuvering', why not make the bridge wheel the main one?
The wheelhouse's wheel feels redundant and foolish: why situate crew and helmsman where they can see forward more poorly?
On the centerline of the bridge, facing the windows, was a helm with the ship’s wheel and a binnacle housing a steering compass immediately forward of it. This wheel was not what could be considered the main ship’s wheel, as it was only used when the ship was subject to frequent changes of course or maneuvering, as would be done near land, in a narrow channel, in port or when docking. When in use it was connected via an overhead mechanical linkage to the main steering mechanism located further aft in the wheelhouse. (This linkage is visible in the photograph of Olympic’s bridge taken by Revd Browne.) Once the ship was at sea under a normal steaming watch, the wheel on the bridge had its linkage disconnected, and the ship was then steered from inside the wheelhouse. If you were standing in front of the bridge wheel and turned to face aft, you would be facing the wheelhouse and be able to see inside it through large windows on its forward side. Those within would have a clear view of everything on the bridge and out the bridge windows facing forward. Inside the wheelhouse was located the main ship’s wheel, and immediately forward of it another binnacle housing a second steering compass. The wheel at this location was connected to a steering mechanism called a Telemotor.
The 1997 movie Titanic portrays these two wheels.