Diana,
It's been my experience that people with voices that are considered "bad" by many voice teachers have made a living as professional performers. What can you say about Louis Armstrong? He was great! Dave Van Ronk, Tom Waits, Leonard Cohen and Mr. Dylan are able represented on recordings. Woody, Leadbelly, many many traditional folk singers have voices that are not considered to be particularly good by many voice teachers. I think that the most important thing a voice teacher can impart is how to save your voice without blowing your cords.

I think that one of the aspects of an acceptable voice is that it contains a "personality".

I haven't encountered a voice that everyone likes, yet.

Frank Hamilton