My response: Two.
Two words, the first one is "you".
The customer buys you first, the first sale that's made is the salesperson.
The first sale that's made is you.
It all begins with the most important person in the world: You.
Once you recognize you, then you can understand the second most important word:...
...The word is "why".
Why leads to the one thing you can't make sales without: Answers.
Why, you, in other words, "Why are you doing this?"
"What's in this for you when you're finished?"
"Why are you involved in this selling profession?"
"What do you have to gain out of it?"
If it's money, get out of sales.
If it's for some greater purpose, you're in the right place.
You're there to help people.
You're there to provide answers.
You're there to provide value.
You're there to learn your best and do your best.
The second part of why is, "Why them?"
"What's in it for them?"
"How do they value?"
"How do they benefit?"
"And why should they buy from you?"
Which leads you to the third part of why: Why ask?
And you can even say, "Why ask 'why'?"
But if you don't master the power of asking questions,...
...you'll never understand the element of engagement.
The two most important words are "you" and "why."
If you master them, not only will you master your sales,...
...you'll master your checkbook.