The marketer must do research. They must know the domain knowledge of the customer, the nuances of how they decide.

Amateur marketers use the knowledge that they selfishly have on the outside. Experienced marketers use knowledge that they gain from the customer. 

Knowledge from the customer themselves and knowledge for what the customer truly experience. 

And you don’t get this knowledge from a customer by asking a clever question- you get it from reading between the lines. Seeing what they don’t do and seeing how they phrase words. Seeing what they talk about, how they breath.

The amateur marketer does no research - the professional does hours and hours before a brief.