Why did Captain Pike leave Star Trek?
Hereof, what happened to Captain Pike in original Star Trek?
Having been promoted to fleet captain, Pike suffered radiation damage as he rescued cadets on training vessel USS Republic, leaving him paralysed in a wheelchair and unable to speak. For these scenes, Pike was played by Sean Kenney.
Keeping this in consideration, why did Pike leave the enterprise?
The real world reasons for Pike's Enterprise departure are a little more complicated. Large chunks of the pilot were repurposed in "The Menagerie" to give Pike his happy ending on Talos IV. Jeffrey Hunter was unwilling to return, so the disfigured Pike was played by Sean Kenney under heavy makeup.
Pike. Best known as commanding officer of the U.S.S. Enterprise NCC-1701, following the ship's original captain Robert April and just prior to James Kirk. Pike counted the top-secret first contact with the natives of Talos IV amid his long Starfleet career.