system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars]why was Sidious so bent on training Anakin if he knew he would eventually kill him?

Sidious stated on two occasions that Anakin would surpass him. Why was so determined to train him if he in doing do would eventually result in his death.
gpt
Feeding his ego, to make him become to his apprentice.

Besides, this is Sith. They got their egos, too.  
 Everyone  knows that the apprentice have killed their master every time in the past.  
Everyone "knows" they will be the one to break the norm.