Precision and expertise: How human intelligence drives our machine learning approach

Expel outlines a transparent, human-in-the-loop ML approach for triaging phishing alerts by classifying automated marketing emails as benign or malicious. Analysts perform structured labeling for each retrain, participate in quarterly performance reviews, and have driven measurable improvements — increasing the model's benign-email recognition from 13.3% to 26.4% since September 2024.