We’ll have to disagree here. The ‘why’ thing is based off scientific research on goal setting and motivation. As such there is an essential distinction from motivational quotes.
A sentence like "How you become unstoppable is finding your 'why' for doing it" is unscientific. That doesn't mean it's wrong, it's just completely open to interpretation. There are too many different ways to refine that idea into a testable hypothesis. So it doesn't mean much to say it's based on scientific research. It doesn't have any bearing on the original comment about vague, facile language.
"Telling people to become unstoppable helps them succeed in starting businesses," on the other hand, is a testable hypothesis, as is "people who believe they are unstoppable are more likely to start a successful business", and that's how interpreted the comments in this thread.