We crave convenience, and we’ll spend money to get it. Almost no one spends their money to make their life harder.
At its heart, convenience is a trade-off between money and time. You give money to get time.
For example, when you buy a module to run for your friends, you are actually buying back time. What time are you buying? The time you would have spent designing an adventure.
It is odd to me, then, that many modules are laid out and organised with seemingly little or no thought given to the GM’s experience of preparing and running the adventure. A badly laid out or organised module tells me the publisher or designer didn’t respect their customers enough to do a proper job. Essentially they gave little or no thought to the user experience.
Remember: it doesn’t matter how good the adventure is if it takes the GM so long to prepare they give up.
I love gaming, and I love running games. What I do not love is spending more time preparing a module than running it. My downtime is precious. I have better things to do than read a module for the third or fourth time in a desperate attempt to understand the plot and the various NPCs’ motivations.
Why make a GM’s life harder when with a little thought and planning, you can make it easier?
When you design a module, think about how a GM will prepare and run it. Make their job as easy as possible. Preparing the adventure should be easy. Running the adventure should be easy. Give the GM the best possible experience. Give them the tools to give their players the best possible experience. If you do that, they will likely buy something else from you. If you do not, they will likely go elsewhere.