NBC didn’t like Majel in the role of Number One—they didn’t think she was strong enough to carry the role. They also disliked Roddenberry’s blatant nepotism in casting his known extramarital girlfriend in a prominent role of a show he was trying to sell them.
If another actress, not connected so intimately with Roddenberry, had been cast as Number One the character might have survived into the series.
Given NBC’s objection to Majel then Roddenberry still tried to sneak her into the show in some capacity.
Was it coincidence that Chapel was on board the ship when it "found" Korby or was it in the Enterprise 5-year schedule -
1. Visit salt creature planet
2. Visit penitentiaries
3. Visit last place heard from Roger Korby.
4. Space mapping
5. Negotiate treaty.
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