A most successful company starts with WHY (from the core of the golden circle), but the others start with WHAT (just like, “If you buy this, you will get this specification”).
The best example can be Apple – Firstly, Apple provides a strong and clear “why”: to challenge the status quo and empower the individual. This “why” is repeated in all they say and do, plus in their products. This clear message helps Apple beat its competitors.