As a music teacher, I have had pure beginners who are 15 years old take up lessons with me. I can tell you that it’s never too late to learn, unless you’re aspiring to become a professional. The only difference between a 16 yr old and a 6 yr old is the amount of school commitments that would limit the amount of time you have to practice. However, there are students who still practices regularly and it’s all a matter of how committed and disciplined the student is.