There are a lot of things people don't love about the Buu Saga, but Vegeta and Goku's growing relationship is the highlight.
Goku has suffered plenty of losses in Dragon Ball, but his worst defeat in DBZ was actually a vital moment for the franchise.
This development boosted the heroes' strength, allowing them to fight back. After Arinsu suggested a way to defeat Gomah, Goku unleashed his Super Saiyan 4 to fight the Supreme Demon King.