Disqualified vs. Unqualified
The term disqualified means to be made ineligible, or deprived of legal rights or powers, including by a law or rule. So, for example, a company director may be disqualified from acting as a director for a period of time if he or she is in breach of particular legislation or rules regarding the conduct of a director.
A person is unqualified if he or she lacks the requisite standard or is unfit for the role. So, if a person who is deemed unqualified for a job, it means he or she is ineligible for it due to a lack of the required qualifications.