Sometimes the author has a pet peeve or some cause they belived it and in their story, they take time to air these views. What was to be fiction turns into a lecture. I've started to red stories like this and I never finish them. The characters can have strong feelings but it the lecture takes over the story, most readers are turned off. Yes, there are great stories that are for one causeor the other but the writer hasn't forgotten the plot to become a preacher.The characters have become puppets to move to the author's desire to prove points. This makes the story less than a story and more of a lecture.
I remember once a friend who told a story and her anger at animal abuse became so engrained that the characters became spouts spewing information that had been researched. The author's world became a political statement. While there are causes I feel strongly about, I try not to let them take over the story.
A reviewer once reviewed one of my books, My premise was in proving a surgeon was inept and shouldn't have been allowed to practice. The reviewer never saw the point. The review consisted of several paragraphs as to how I should have written about the doctor's treatment of women. Did I miss that point. Not really. There were subtle mentions but my real goal was to show the harm he did with his surgeries to people, not a femals soap box.
So don't jump on that soap bok and forget about the story or turn your characters into puppets who expound on the wrongs they're talking about.