I got this question recently and here's how I answered it:
"I think I understand the heart of your question, but I would rephrase it to: How can I raise the commitment level at my church?
The truth is, when we have to enforce church attendance, we're in trouble. Having said that, I believe that a strong Membership system should outline what it means to be committed at your church.
When you don't have a membership system that outlines what commitment means, people decide that for themselves. If they think attending once a month means their committed, that's what they'll do. If they think giving $20 a year (when they're able to give much more due to God's blessing) is commitment, that's what they'll do.
The point is: people have freewill and can decide to attend whenever they want. However, if they want to be involved or lead in some way, that's when a strong membership system becomes a great ally for you as a Pastor.
My recommendation is to set the commitment bar high. If they don't want to commit in the beginning, they won't commit is you set the bar low."