system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] Why didn't Voldemort make more horcruxes when he gained a body?

He was already down 1 with the journal getting destroyed by the time he gets a body, so why didn't he rush to make more? It would have secured his immortality a little bit more.
gpt
In the HP universe, it is believed that the number 7 is the most magically powerful number. So Voldemort believed that having a seven-part soul would give him some unknown, unforeseen power.

He had a six-part soul the night he tried to kill Harry. Lily's protective charm caused him to lose his body, and because his main soul was so fragile from the repeated murders and creation of Horcruxes, his soul split again, causing him to then have a seven-part soul with the extra part latching onto Harry (though Voldemort believed he still only had a six-part soul).

During Chamber of Secrets, the diary was destroyed, lowering Voldemort down to a six-part soul even though he believed that the diary, rather than Harry, was contributing to that six-part soul.

At some point before the events of Order of the Phoenix (likely between getting his new baby body and his new adult body), he turned Nagini into a Horcrux. Voldemort believed he had a seven-part soul at this point even though he didn't realize that the diary was gone or that Harry had a piece of his soul in him.

At some point between getting an adult body and the events of Half-Blood Prince, Voldemort learned that the diary had been destroyed, which made him believe he only had a six-part soul, not realizing that Harry carried a portion of soul within himself and that he actually still had a seven-part soul.

It's unknown why Voldemort didn't make an eight-part soul for himself believing he was restoring his seven-part soul, but it's possible that it's harder and harder to create new Horcruxes as you create more, and therefore he decided it wasn't worth pushing himself back to that point when he already considered himself the most powerful living wizard in the world (especially after Dumbledore's death), or if he tried and was physically unable to create another, or if he just decided he would do that once he had taken out Harry.