freeza's pride killed freeza lol.
the face of goku afterwards, only goku can be sorry for kill his enemy lol.
but he did gave him lot of chances, so even if frieza's attack wouldn't kill him, goku had no choice but to kill him so at least he will die with regret.
or at the very least, since he gave him super sayan chi, it's capable of killing goku as much as goku could done it, sound logical too,
that's also kinda answer your question @Terrestrious
hope i can sleep lol, i have read now dragon ball for hours, it's 4:30am ><
one chapter and that's it i guess, it's the end of the arc anyway.
oh and the grand elder death, it was so star wars'shi xD