Three-part modeling: morning prep time

Modeling subject: the time it takes you from the moment you open your eyes in the morning until you leave the house. Some days 40 minutes, some days 70 — what makes that difference?

Build 'morning prep time' as a three-part model: input → relationship → output. (1) Output: define in one line what you're trying to predict (e.g., minutes from waking to the front door). (2) Input: pick only the 2–4 variables that move the output the most. (3) Relationship: write in one sentence how the inputs combine into the output. You may write it in words or as a rough formula. Finally, you must state at least one 'variable you deliberately excluded' and why, plus one 'situation where this model won't fit well.'