A malakah is a stable, cultivated disposition enabling a person to perform an activity with relative facility and consistency. Merely repeating a memorized sentence correctly does not establish full command of the skill.
A student may recite one eloquent passage, yet struggle to form a new explanation with sound vocabulary and syntax. The recited passage may be eloquent without proving the student possesses speaker-level eloquence.
A proficient speaker can respond to unfamiliar questions and communicate varied ideas without losing linguistic soundness. This repeatable capacity is the essential distinction conveyed by malakah.