This is similar to my experience. When I was still teaching publicly, like Gerry, I found that if I had to recruit and "sell" the art, I got more people in the door ....who would only drop out when they found that we taught slowly, more or less in the traditional way my sifu had taught me.My first-lesson dropout rate was really low. But that's mostly because I rarely had new students. My availability and visibility meant by the time someone found me, they'd gone through some trouble. At that point, they're likely to last a few months. When I did seminars to generate interest and new students, the first-lesson droupout rate was higher.
Now, I consider myself retired and teach an even smaller, private group. I still get a few calls, but I tell them up front that "what we do isn't for everyone". I give them a location and time to try a class . Very few show up.
Works for me. Training beginners can really drain your energy and time.