"Miscalculations. Or some sort of disturbance in the time stream, which is more likely. Those are impossible to predict, and there's no way I could've worked that into my projections. Doing the math for something that has a one in a trillion chance of happening on a scale that ranges from nothing to world-ending is like asking a rock to write a research paper. It's just not going to happen. I mean, it could, but you'd basically be spending the rest of your life working out the details of every single what if scenario."

And nobody had time for that, which is why Bulma willingly sent her son into the past knowing that one of those what ifs could happen and she'd lose him forever. But things had gotten so bad that a chance at making things better was worth the risk.

"I've been working on repairs, but this world... kind of leaves a lot to be desired. I'm having to make modifications. A lot of modifications."

Good thing Briefs are like MacGyvers. They can build anything out of nothing.