Rabbi Lebor from Shaalvim (who was my old bar mitzvah teacher, decades ago in Woodmere) asks and answers a few questions, but I am not certain that his answers are correct -- but in truth, I am not certain that they are wrong either.
First, Rabbi Lebor tells us that "While every Yeshiva has some alumni that are not observant today, the numbers are really very small." In truth, I do not know what they numbers are, and I am uncertain if he does either. How many of the graduates from any given Yeshiva are still observant is an unstudied question. An even better question that is completely unstudied is to know whether some yeshivot have higher or lower retention rates, and an even better question would be to control for entering religiosity, so that we can really understand which institutions do a better job with which kinds of people. I think that the exit rate from Orthodoxy is much higher than we acknowledge in all the communities, and while we all like to speak about the entry rate, almost no one wants to closely examine the exit rate. Indeed, I suspect that they same phenomena that bring some people in, drive other people out, and that is a very complex problem.
The second claim that Rabbi Lebor makes is that "both skills in learning and general knowledge are sorely lacking" (presumably in comparison to something). I also have my doubts about this, although I also note the near total lack of empirical data present as to what day school and high school yeshiva graduates ought to know. My experience with graduates of Israeli post high school yeshivot is also sometimes disappointing (and to be honest, college graduates in general), but since I do not have a base line, I have a hard time drawing any real conclusions. Perhaps his and my expectations are too high. Truth be told, I encounter musmachim of a prominent gadol in Israel who regularly disappoint me in what they know, but always inspire me in their personal piety. Is this bad? I am not sure. What is the goal of semicha?
Finally, Rabbi Lebor tells us that "Kids today are prouder and more desiring of their Judaism than in years past" but I have my doubts that any of this is true -- and this goes to the heart of what are the goals of chinuch. I complained a few years ago to the director of a women's seminary about how little the girls learn all year. She was totally not bothered by my observation. She told me that the goal of her seminary is to convince the girls to move to Israel, and not to actually teach them anything, quoting to me the Ramban on Chumash that there really are mitzvot only for practice in the Diaspora.
What she meant, I suspect, is something that I have since heard a few times in many different yeshivot -- a direct challenge to my idea and ideal that Yeshiva is a place to sit and learn Torah. The claim is made that the real purpose of Yeshiva is to (pick one) (1) make kids frum. (2) Make kids frummer. (3) Make kids want to live in Israel. (4) Make kids want to serve in the IDF. (5) Make kids to not want to serve in the IDF. (6) Make kids want to go to YU for College. (7) Make kids not want to go to YU for college. (8) Make kids want to support their Yeshiva as adults (9) Many other goals.
Since we have no agreement on goals, measuring outcomes remains very hard -- and even when we agree on goals, no one actually wants to closely study what works, as that will certainly undermine some beloved institutions. So we have claims with no data.
MJB
Michael J. Broyde