Occam's Razor
Among solutions that work equally well, prefer the simplest.
Why it matters
Each extra element adds something to learn, maintain and get wrong.
How to use it
- Remove elements one at a time until the design stops working.
- Question every field and option.
- Prefer one clear path over several.
Example
If a form works just as well with 3 fields, the other 6 are only adding effort.