What the sidebar tracks.
Each goal has words the sidebar shows and a way to complete: an event, a number variable reaching a figure, a yes-or-no check, or a step that completes it by hand. The challenge is won when every goal is complete.
Winning and losing.
A step can win or lose the challenge outright, with a reason everyone sees. A time limit loses it when the clock runs out, unless every goal is done by then.