The nice thing about mathematics is that you can easily do it outside of school and independently, and when you do it as a mature adult, you do it because you love it and for no other reason. You are free to use better texts than you could as a student, so if you want to brush up on calculus, you can use Spivak or Courant rather than being forced to use low-quality texts that are optimized for the convenience of the professor rather than the insight of the student. There are also so many learning resources available now that weren’t available when I was a student—things like wikipedia, planet math, and physicsforums.com, not to mention software like Octave and Sage.
The nice thing about mathematics is that you can easily do it outside of school and independently, and when you do it as a mature adult, you do it because you love it and for no other reason. You are free to use better texts than you could as a student, so if you want to brush up on calculus, you can use Spivak or Courant rather than being forced to use low-quality texts that are optimized for the convenience of the professor rather than the insight of the student. There are also so many learning resources available now that weren’t available when I was a student—things like wikipedia, planet math, and physicsforums.com, not to mention software like Octave and Sage.