BACKGROUND: This paper reports the results of the treatment of our first 200 cases of lumbar disc herniation and foraminal stenosis using full-endoscopic transforaminal lumbar discectomy (FETLD). We analyzed outcomes and radiological parameters to overcome failure and inappropriate indications and also highlighted the red flags for surgeons coming to this field as well as the pathways to success. METHODS: Data on endoscopic procedures were retrospectively analyzed between October 2018 and March 2023. We abstracted sex, age, leg pain by NPRS, postoperative satisfaction according to the MacNaab score, postoperative surgical complications/adverse events (≤30 days), and history of any previous surgery. Furthermore, we measured different radiological parameters to determine the grade of stenosis or discopathy. RESULTS: Once the learning curve was completed, patients' satisfaction increased to 94%, with only a small percentage (6%) of patients unsatisfied 30 days after the operation. Perioperatively, 33.5% of the patients experienced mild to moderate transitory paresthesia. Univariate analysis showed a tendency toward a higher risk of failure in those patients with degenerative listhesis (odds ratio [OR] 4.8, 95% CI 0.97-23.9, P=0.055) as well as those with severely degenerated discs (OR 8.7, 95% CI 0.96-79.4, P=0.054). Conversely, the chances of failure seemed to be lower in patients with severe foraminal stenosis. CONCLUSIONS: FETLD proved its efficacy in treating several degenerative spine conditions or was useful for avoiding previous scarring in patients already operated on to the same extent. Therefore, FETLD can be safely used in patients with comorbidities, the elderly, and when the invasiveness of an open technique is not suitable.