I am often asked why MO schools have charedim as rabbeim and not MO rabbis. To put it another way, as Rabbi Riskin and Rabbi Lamm asked, why aren't there more MO mechanchim.
I'll answer with the story of my closest friend. Ari is a doctor. He is a ben-Torah in the best sense of the term. He's honest, modest and caring. He's serious about learning. So much so that he took off time from med school to learn. He's a talmid chacham, and a better thinker in Torah than I am. Like myself, Ari was an advisor in NCSY. He was well liked by the kids, and liked them. He's funny and personable. In short, he would have been an amazing mechanech.
So why did he not take that path? I can't say for sure, but I can offer some possibilities. Despite coming from a frum MO family, I doubt his parents ever encouraged him to take that route. Knowing the challenges that such a choice would entail, they might even have discouraged him had he asked.
Though Ari did not grow up rich, he was comfortable enough. Someone who grows up that way does not easily embrace a lifestyle that involves financial hardship.
Unlike his charedi peers, Ari's secular education left him with many choices professionally.
He grew up in a world where frum bal habos, is not only not an oxymoron, but a respected l'chatchila choice.
Or maybe he just wanted to be a doctor.