unskillfulness

noun

1. (uncountable)The state or quality of being unskillful, of lacking skill

   “Grammar is perhaps the most comprehensive of all studies; but it is chiefly owing to the unskillfulness of instructors, and to the errors and defects of the systems in use, that it is commonly regarded as the most dry and difficult. 5. "”

   “Thirteen years later, a variety of causes, some of which will be unfolded in the course of this narrative, had contributed to irritate the impatience of the nation, while the unskillfulness of the existing minister had disarmed the royal authority.”