Although in some areas this may be true, the stats do indicate that it is worth the church’s while in the global spectrum, but even if it only helped one more soul than if there were no proselytizing, that perhaps would still be seen as a gain. However, trade-offs are more complicated than just what the stats show. The efforts aren’t perfect, but they’re still worthwhile for the church.
I think in areas where the missionaries work on public relations and morale more often (rather than purely tracting and such) things probably go better with the public (sounds kind of obvious, I know). I mean, when missionaries do service in the community and help people out, I think that helps a lot with people’s impressions. What the members of the church and the church itself does is also important. In many cases, what the missionaries do is up to them, but some missions have required amounts of time that they have to spend on certain things, and the results of that, I think, are often products of the faith that went into it (as well as the faith of previous missionaries in that area—which may have been negative, in some cases). Faith is up to the individuals. Not every missionary is extremely faithful, but some are. Some missionaries cause a lot of damage. However, even when a lot of faith and love goes into it, that doesn’t mean they’ll end up baptizing five thousand people that month or whatever. Sometimes results take generations to sprout, but faith is rewarded (not always in expected ways, either).
It’s not true that being a missionary is a rite of passage. Sure, there’s stigma for not having been a missionary (although this has lessened in recent years), but just because you’ve been a missionary, that doesn’t really guarantee you anything, anymore (maybe it seemed to for a lot of people, once). It’s pretty much selfless service, unless they do it because of family, stigma of not doing it, personal growth or whatever. I don’t feel that I’m any more likely to garner interest from an LDS girl after having served a mission than I would be from any other girl if I weren’t even LDS. In fact, it’d probably be easier to get a non-LDS girlfriend, just because LDS girls have such high standards (and not just in religious regards, but also with education, perceived capabilities and so forth). This is especially true in areas like BYU where everyone and their dog has served a mission and has a couple degrees (it doesn’t really seem like anything special, you know). However, my odds might be even less than that had I not served a mission. So, basically, what I’m saying is there’s just too much competition to call it a rite of passage. I guess in areas where there aren’t as many people who serve missions things might be a little different in the sub-culture.