system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] If Darth Sidious wanted a strong apprentice so bad, why didn't he just fuck someone and have children whom he can train?
gpt
A strong apprentice was always his Plan B.  Plan A was always the Rule of One, with himself cloned and ruling forever.  Children would undermine that plan.

The Plan B was there just in case something interfered with Plan A.  Sidious originally wanted Anakin because he could be powerful enough to overthrow him, therefore he wanted Anakin converted past the point of no return and fully committed to the Sith tradition.  Once Vader was crispy-fried and in the suit, and Sidious had his clone bodies, Plan B became drastically less-important, and it was sufficient to have a powerful enforcer to enact his will.

It was only when Luke appeared on the scene that Plan B regained any real importance.  Then Sidious was looking at a younger Skywalker that had lost little (if any) real potential, and could potentially defeat both Sidious and Vader.  Not only that, but Vader may have conflicted loyalties once Luke came into play.  At that point, it was necessary to ensure that Vader kill Luke (he could not be allowed to take him as an apprentice), or convert Luke to the Dark Side by getting him to murder his own father.