First-Principles Teardowns
Why is it shaped like that?
We take an object you've held a thousand times, trace every part of it back to the constraint it answers, then break one constraint on purpose and redesign it. It's the best product-sense workout there is — and it's exactly what "design a ___" interview questions are testing.
The series
The method, in five moves
Every teardown runs the same loop. Once you internalize it, you can do it on any object or any screen — and it turns interview prompts from traps into open goals.
- Name the user and the moment. Refuse to design the generic object.
- Separate the obvious job from the jobs that create trade-offs.
- Trace every feature back to the constraint it answers. Nothing gets to be "just how it is."
- Notice which constraints are interfaces to systems you don't control.
- Break one constraint on purpose and follow where it leads.
Start with the water bottle — it's the fully worked example.