Prahladananda Swami : Once the gurukula students were reciting verses from Bhagavad-gita. One of them, Lila-smarana, had a good memory. Although I wasn't living in the temple, I was also memorizing Bhagavad-gita verses, because if you knew a whole chapter then you'd get a whole plate of maha-prasadam. I was trying to keep up with the gurukula students so I could get a maha plate also. When this little boy recited many verses I thought, "Wow, this is fantastic! He's expert!" Prabhupada asked him, "So what is the translation?" Lila-smarana said, "I don't know." Prabhupada said, "This is useless. They must know the translation." Then I realized that I also have to know what the verses mean. It's not enough to simply parrot the words.
Reference:Memories Anecdotes of a Modern Day Saint - Volume 1 by Siddhanta Dasa