I hate to make people feel down... but i think some people's voice sound better than others....
I believe there is such thing as vocal talent, since our voice is as much a physical element as our body. It's like saying, is there such thing as good looking people, and yeah, you look at the actors and actress, with nice shapes and good features, but then some will say everyone is beautiful, i would say, yeah!! beautiful in their own way, but not good looking....
So when it comes to voice, there are people who doesn't need too much vocal training, their voice quality is already good and get praises throughout. Then with some training, their voice gets better....
But there are those whose voice really cannot make it, everytime they sing, people criticise or laugh, some try not to laugh in front. Then people tell them their voice can actually be great if they go for proper training. Yes, their voice can improve with training, but to be great????
Can't blame the schools for thinking this way, they need money for their bread and butter right???