The primary goal for the Business visa (B1 visa) interview is to verify all information presented in the application and to make sure that ,you (applicant) is indeed visiting USA for Business purpose and has a valid case, also applicant has enough ties back in your home country and the person will come back after the visit to USA. Expect questions targeted around the business and employer specific, purpose of the trip , proof of fund etc.
Following are the commonly asked questions during the B1 Business visa interview