Background: Although surgical shoulder stabilization via coracoid transfer in collision athletes is effective and has a low reinjury rate, the factors affecting poor clinical results and the superiority of the 2 stabilization procedures (Bristow and Latarjet) remain unclear. Purpose: To explore the factor(s) affecting poor clinical results of coracoid transfer in a large cohort of rugby players and to compare postoperative function between the Bristow and Latarjet procedures. Study Design: Cohort study; Level of evidence, 3. Methods: This study included 169 consecutive shoulders of 154 competitive male rugby players who underwent shoulder stabilization surgery (Bankart repair with coracoid transfer) between 2014 and 2018 and had a mean follow-up of 2.7 years (minimum follow-up, 2 years). The Bristow procedure was performed in the first 92 shoulders (84 players), and the Latarjet procedure was performed in the latter 77 shoulders (70 players). A poor clinical result was defined as a postoperative Rowe score of <70 and a postoperative Western Ontario Shoulder Instability Index (WOSI) score of >630. Multiple logistic regression analysis was conducted to identify the factors affecting postoperative functional failure. The postoperative scores and complication rates were also compared between the 2 procedures. Results: In total, 92.3% of the rugby players returned to their preinjury competition level at a mean of 5.9 months postoperatively. The Rowe and WOSI scores showed that shoulder function was improved postoperatively compared with preoperatively. The number of rugby players with a poor clinical result was 18 (10.7%). Multiple logistic regression analysis demonstrated that a poor clinical result was associated with a preoperative glenoid bone defect of >20% of the glenoid width (odds ratio, 9.8), whereas the clinical result was unaffected by the type of coracoid transfer. There were no differences between the 2 procedures in any of the postoperative scores or complication rates. Conclusion: The present study indicated that the most effective predictor of postoperative functional scores was the degree of the glenoid bone defect and not the type of coracoid transfer. This information may be useful for the strategic treatment of shoulder dislocations in collision athletes.