Jai Sri Ganesha,
The truth of meditation lies in potency of concentration that a process of recollecting the scattered mind at its optimize pitch,
But concentration is not alone the prime factor in meditation, it is just an initiative skill to bring mind back to self,
Prime subject of the meaningful meditation is inner journey in quest of God within,
If an porter fix the mind on his job may yield better result, so is the truth of earnest aspirants in meditation to relocate self in proximity of God,
Jai Mahadev