Cobalt, with its negligible overpotential, has great potential as a theoretically ideal HER catalyst, due to its ability to form stable Schiff base tetradentate ligands that enhance its electrochemical properties. Nickel, relatively fair overpotential, remains a viable and cost-effective option for practical applications. However, the extraordinarily low overpotential of cobalt requires further investigation to validate its performance and clarify its potential for real-world HER applications.