According to Health Care Risk Management standards supported by ASHRM and patient safety principles endorsed by The Joint Commission, the most likely root cause of medication errors is system or process failure. Modern patient safety frameworks emphasize that errors rarely result from isolated individual mistakes. Instead, they typically arise from weaknesses in processes, workflow design, communication systems, technology integration, or inadequate safeguards.

Illegible handwriting, manual systems, and look-alike or sound-alike drugs are recognized contributing factors. However, these elements represent components within a broader system. For example, illegible handwriting becomes problematic when standardized order entry systems are lacking. Look-alike medications pose risks when storage, labeling, or verification processes are insufficient. Manual medication delivery systems increase risk when redundancy and double-check mechanisms are absent.

Root cause analysis methodologies consistently demonstrate that unsafe system design, poor communication processes, lack of standardized procedures, and inadequate training contribute to medication errors. A systems-based approach aligns with just culture principles and focuses on improving processes rather than assigning individual blame.

Clinical and patient safety objectives emphasize system redesign, standardization, and continuous quality improvement. Therefore, system or process failure is the most likely root cause of medication errors.