Aaron did so; he kindled the lamps toward the center of the Menorah, as G-d had commanded Moses.
Numbers 8:3
Moses only told Aaron that the wicks should point toward its center branch when he is kindling them. Once they are burning on their own, however, the wicks did not have to face any particular direction. Yet, when Aaron lit the Menorah, "he kindled the lamps toward the center of the Menorah," meaning that he ensured that that the flames continue to face the center of the Menorah even after they were burning steadily on their own.
Aaron's behavior demonstrates an important lesson in our relationship with G-d.
At the beginning of our relationship--when we are first igniting the flame of our soul--it is easy to face the center, to keep our eyes on G-d's exact instructions. But once we become more advanced--once the flame is burning steadily--we might imagine that we, too, are authorities on spirituality, on the proper method of accomplishing G-d's purposes, and direct our enthusiasm in any direction we see fit. Aaron realized that even after the flames are burning--after we have reached lofty heights in our Divine service--it is important to remain focused on G-d's agenda, with the naïveté, sincerity, and devotion of a novice.
—from Daily Wisdom 3, P. 290