Controversy still exists about Breeding Soundness Examinations (BSE) and what they can and cannot do. At times they are not used because of a lack of understanding of their value while at other times they are used with unrealistic expectations. First, BSE is performed to identify bulls with reduced fertility not just to find those which are sterile. Very few bulls are sterile but a significant percent have reduced fertility.
Bagley, Clell and Burrell, Craig, "Understanding Bull Breeding Soundness Exams" (1997). All Current Publications. Paper 407.