Clients dropping off

Is it normal for clients to drop off from coaching program? I offered free 10 week coaching program. Almost 20 people enrolled and I did 2-3 calls but now all I have remaining is 7 clients who are still on the program.

The thought I am having is “I am not a good coach. They did not get any help from my offer so they dropped off.”
Is it something to do with my coaching skills or people are not interested in coaching at all.