ZD – what you’re talking about is something that is not only true today – it has always been an issue in kiruv.
I remember reading a story that took place years ago that had to do with that concept. It was something about some people (I think Yeshiva bochurim) who were involved in some kind of kiruv initiative for not-Frum kids. I guess they felt like they weren’t being successful, so someone (I think maybe their Rosh Yeshiva) had to explain to them that people don’t become Frum in one second, and the goal is that one day their grandchildren….. (I don’t remember exactly what he said, but the point was that you are kindling a spark).
I think he also pointed out that the previous generations didn’t stop being Frum in one second, it was a process, so likewise, you can’t expect them to become Frum in one second, it is also a process.
Also, I think the point of having someone put on Tefillin is just that – that they should put on Tefillin one time.
If we appreciated the value of Mitzvos, we would realize what an incredible accomplishment it is when a Jew puts on Tefillin one time, and we would realize what an incredible effect he is having both on himself and on the entire world!