As one of the previous posts reply pointed out, the B.A. in mathematics can lead to anything: from M.D. to M.B.A, to some kind of engineering or actuarial degree. The really difficult question is how do you encourage your students that Ph.D. in mathematics might still be a good idea, even if they might not like teaching or unsure about their research skills. Essentially, you have to tell them there is plenty of demand for mathematicians in the industry or the government (think NSA, CCR). This is also suggested by this ranking, btw. Unfortunately, in the past few years there has plenty of drum against going to grad school (see here, here, here, and somewhat less applicable but still strongly worded followup here). So how do you respond?
My answer is trivial: start early. While in graduate school, take advanced classes in CS, applied or numerical math, finance, or economics. It is often easy to cross register at the business school, but very few people ever do this. But you don't even have to do that - the lecturer might allow you to just audit the class. If things work out, you succeed in mathematics and become a professor, you will know what to say. But if things don't work out, you will know what to do...
