The "inconvenient truth"
I've come to believe that although Salvation is free, sacrifice and service are to following Jesus what "diet and exercise" are to losing weight and being fit.
The "inconvenient truth" is that you can spend hours at the gym eating Twinkies but unless you are sweating and feeling some pain you are not going to get in shape. You can read every fitness "bible" in the world, but unless you put what you learn into practice...you may actually be gaining flab from all that reading. You might get a "free shot" to win the prize on the "Biggest Loser", but if you ever watched the show you know how much "work" is involved. The FDA has yet to find a "diet pill" that would actually do anything without proper diet and exercise... Likewise, there are simply no substitutions, no quick fixes, no "magic pills" that will allow us to live a life of significance without first giving ourselves over to a life of serving God by serving others and sacrificing "our will" for Christ's.
So how do you "market" a lifestyle that clearly involves personal sacrifice and "pain"? You better have examples of people transformed and "being transformed" in a positive way by following Jesus!
If you don't, people will be far more interested in "buying" diet pills, gym memberships, and exercise books...because even though they don't actually work...they take so much less "effort".