I suspect you understood exactly what I meant; nevertheless, I don’t mind explaining.
Fact: Many people credit Kiruv organizations with introducing them to Judaism and making them frum. (Although I am not, and never have been, employed by any such organization, I know many such people personally, just from my own community; if you don’t, feel free to do some research). It is simply not true that no one ever became frum because of a kiruv organization.
Yes, what you say is true, that Hashem gives everyone their opportunity to recognize the truth. Why do you think that the organization’s efforts were not the way He chose to reach out to these people? Why do you assume that, had they not been receptive to the organization, they would have been given another chance, and that they would have capitalized on it? In any case, we are not allowed to operate on the assumption that “Hashem takes care of it” when it comes to helping others. We are to assume that our efforts are necessary and critical, even as we recognize that ultimately Hashem will see to it that everyone gets what they need.
Plainly put, we can not think about “how would it have happened, if it had not happened the way it did.”
The assertion that “no one ever became frum because of a kiruv organization” necessarily discourages people from contributing to kiruv organizations. This would obviously compromise the organizations’ ability to bring back as many people as they otherwise would be able to do. Therefore, the assertion is an attack on the neshamos of those who would potentially be excluded from kiruv efforts because of lack of funds.