What are the limitations of Expert System ? Explain briefly.

Limitations of Expert system Expert systems are sometimes overrated. Expert systems can be expensive to develop and maintain. It is difficult to elicit the knowledge of experts. It lacks common sense. Expert system cannot learn of its own. Expert systems do not have a wide application and hence are not extensively tested. Their scope is limited to narrow problems or providing focused solutions. Possibility of Error. Require Inputs in a sophisticated format and cannot readily deal with 'Mixed' knowledge or crude user input. The validation of expert systems can be difficult.