Having or showing no skill; clumsy. (Oxford Dictionaries)
Without skill or aptitude for a particular task or assignment; maladroit: (Dictionary.com)
Generally awkward or clumsy; haplessly incompetent. (Dictionary.com)
Inappropriate; unsuitable; out of place. (Dictionary.com)
Lacking in fitness or aptitude: Unfit. (Merriam – Webster)
Lacking sense or reason: Foolish. (Merriam – Webster0
Not suitable to the time, place, or occasion : inappropriate often to an absurd degree. (Merriam – Webster)
Generally incompetent: Bungling. (Merriam – Webster)
Not skilled or effective. (Cambridge Dictionary)
Barnaby Joyce throws Coalition into crisis over PM’s ‘inept and unnecessary’ attack.
The more inept you are the smarter you think you are.
Unethical and inept? The influence of moral information on perceptions of competence.