Regarding such practice, one of the earliest grammarians, Yaska (6th–7th century BCE), wrote: «Reciting mantras without understanding their essence is the same as offering sacrifices to extinguished embers rather than to the fire».
In the context of classical yoga, «japa» is a special practice of repeating mantras with deep textual analysis. This term has undergone significant changes in its meaning compared to its original sense. However, regardless of the context, «japa» involves the verbalization of mantras. A mantra is a unique energetic text. But for a holistic person, what they say is always energetic because they are sincere and do not speak unnecessarily. Similar to a poetic work that, even though written by a person, becomes a source of inspiration for many through quotations, mantras are also initially recited by individuals experiencing higher states of consciousness, and then they are used by those who are striving for such states.
«Yoga: History of Ideas and Views», Chapter 4 «Yoga as Union»
This refers to the kind of execution that is not a practice of yoga, for example, repeating a mantra like a prayer (without knowing its meaning and without aiming for any state that the mantra evokes).
Another approach to performing mantras can be attributed to a religious perspective — a magical perception of mantras, where the words of the mantra are treated as those that fulfill the practitioner’s desires.
Mantras as incantations are mentioned in the Goraksha Paddhati.