El artículo Problems with automatic accessibility testing presenta un buen análisis de los problemas que presentan las herramientas automáticas de evaluación de la accesibilidad web:
Automatic testing of software is brilliant. Saves a lot of time and effort, prevents problems soon and makes our products better. But when trying to automatically test accessibility we need to know about the challenges and problems before. Some tools may even produce wrong results and some tools may report everything is perfect when they can only test up to a third of criteria.