I will say that I think it's possible for someone to be committed, but simply not understand how much knowing the music can help you, (and thus haven't been listening to the music very much). In this situation, it's not so much a lack of commitment, but more the lack of proper tutelage.If you love tango music and want to dance, you'll dedicate yourself to it. It does make a difference in how one dances.
I'll also add, that if the person has a strong music background (played musical instruments, sang in choirs, etc.), I don't think they will need as much time listening to the music, as someone who doesn't have that background.
My two cents.