T-Rex: This planet is crazy. I leave out a bowl of spaghetti because I was gonna clean it later and just forgot, which happens all the time to the even most responsible of adults and they should not be made to feel bad about it, and three days later -
T-Rex: - there's mold in it!
T-Rex: Life's EVERYWHERE, man. I throw down some dirt and plants start growing. I leave some water out and microbes are like "cool, time to poop in this or whatever it is we do". Sterile environments are hard to create and harder to maintain, because life is GAGGING for a chance to get in there and spread all over the place!
Utahraptor: You see life as... an infection?
T-Rex: You could! One that's OUT OF CONTROL!
T-Rex: There's extremophiles that live in acid, in deserts, on the ocean floor, and under Antarctic ice. You know how hard it'd be to wipe ALL life from the planet? It's RIDICULOUS. Super expensive.
Utahraptor: This sounds like super villain talk, dude!
T-Rex: Hah hah! What a ridiculous allegation!
T-Rex: 〚thinks〛 THE TIME TO READY THE DOOMSDAY ENGINE HAS ARRIVED