Some visa applications require further administrative processing, which takes additional time after the visa applicant’s interview by a consular officer. Applicants are advised of this requirement when they apply. Most administrative processing is resolved within 60 days of the visa interview. When administrative processing is required, the timing will vary based on the individual circumstances of each case.
If your visa has been denied, you may find useful information on Ineligibilities and Waivers on usvisas.state.gov.