Ineptitude (noun)

1. The quality or state of being incompetent or ineffective; lack of skill or ability.
2. The state of being unskillful or unqualified.

Origin:

From the latin word "ineptitudo" meaning unfitness or incompetence.

Examples:

1. The inaptitude of the new employee was evident in her first day on the job.
2. His inability to complete the task was a clear indication of his ineptitude.
3. The singer's voice was weak and off-key, revealing her ineptitude as a vocalist.
4. The team's poor performance was due to the ineptitude of their coach.
5. The company"s financial troubles were a direct result of the CEO"s ineptitude.