Who Was More At Fault?

[Yoshi]

When it came to Cell becoming Perfect?

 

[Giga Hertz]

Krillin genuinely felt like he was murdering someone who hadn't necessarily done anything overtly wrong.

Vegeta wilfully did everything in his power to ensure Cell's perfection. While Krillin had the opportunity, he was also trying to prevent it through other means.

 

[Yoshi]

Yeah, and in the context of the actual story, Piccolo even mentions to Bulma that Krillin broke the remote and after saying that he also said that Vegeta ruined everything.

 

[Beerus]

I want to blame Krillin but Vegeta is easier to blame because his ego and arrogance is as bad as Goku's stupid fighting nature sometimes.

 

[Yoshi]

Vegeta letting Cell become Perfect may actually be as bad as Goku giving Cell a senzu bean now that I think about it.

 

[FruityPebbles]

The whole arc was Goku's fault for not stopping Gero from making the androids, anyway.

Actually, he could have stopped Cell from becoming Perfect altogether if he simply trained in the ROSAT with Gohan before Vegeta and Trunks did. Not like he needed to tell Vegeta about the ROSAT, anyway.

Still, Vegeta was the only one who actively helped Cell to become Perfect by not only letting him go but stopping Trunks from killing him.

 

[Yoshi]

They were all at fault for not listening to Bulma’s advice on how to kill Doctor Gero to prevent anything at all from happening.

 

[Majin Blaze]

So, I am a huge Vegeta fan, but I got to give him the slight edge here, because he honestly could've just ended Cell, but he let his ego get in the way, and wanted to prove he could beat Cell, even if he became Perfect.

Krillin where if he just pressed the remote, and ended 18 right then, yeah it would've probably helped but also, who's to say that if that happens, Cell doesn't end up doing what he did after he spit her up later and try to blow himself up with the planet when he see's he can't win now. Goku wouldn't have been able to Instant Transmission Cell away, and they are all screwed.