The big thing that I can tell is that most of the adventures are designed by a team of authors who don't know what the others are doing. And the editors aren't doing their jobs to make sure there is a unified theme and that things work together.
They will give assignments to work-for-hire writers and then just glue the individual chapters together, creating uneven tone and challenge, in a flavorless book made as cheaply as possible.
They will give assignments to work-for-hire writers and then just glue the individual chapters together, creating uneven tone and challenge, in a flavorless book made as cheaply as possible.