In college, I worked as a teaching assistant for an introductory programming language. For most of the people in the class, this was probably their first and only programming class.

One day, I was doing program code reviews with a handful of students. This one girl gave me her code, and, after looking at it, I asked why she had repeated a certain line twice:

let x = 7;
let x = 7;

She said, "Just in case it didn't get set right the first time."