Disclaimer: I am the project leader of OpenLP, but I have tried to be unbiased in my article.
Have you ever been in a church which just got a data projector to use for its services, and then all they do is use PowerPoint, even though you can see it's not suited for the job? Have you ever wondered if there are other solutions?
Perhaps you've investigated other solutions and come across some commercial applications, but you find it difficult to cough up $400 for this application.