Too often singers want the magic answer... "am I talented enough to make it?" Students may feel like they don't want to pursue singing lessons unless they know they have a chance at success. No one can predict the future. True, some singers are naturals and come with a great starter package, but even those singers may show relatively little improvement week after week. Some of my 'weaker' or less experienced students have taken initiative and made great strides as well as achieving great rewards! As a voice teacher, I make assessments, corrections, and offer tools to improve. I hear what is and what could be. I hear potential. But I merely serve as a guide to my students. With out the desire, the work ethic, or the ability to process and apply the information a student will see minimal improvement. Maybe the real question is do you want to improve?
If you like sing and have some basic skills and a desire to improve, then sing! If you apply yourself, you will see success when given the necessary tools and techniques. (I think the concept of learning to cook will serve well here. If you are not a natural in the kitchen and have trouble understanding basic concepts of pairing foods, combining spices, or measuring properly, you won't make it too far on you own. On the other hand, you can learn to cook pretty well, if you take some good classes, understand basic techniques, and hone the skills you learn. You may not become a world famous chef, but you could please a palette here or there!) Just remember, even some singers who were once told 'not to quite their day job' have built good singing careers by applying a good work ethic.