The church is man-made. In my experience, it was harder and harder to ignore as time went on. The BoM was complied by a "prophet," one of many in his area in his time, the church is led by men who are constantly changing its course, the promises of the church are so selfish, and the tactics used to keep people in are such that no god would ever employ them. The mormon church is not ran by the god the scriptures describe, it is run by men who only care about membership and tithing.
There were three big shelf breakers. The first was the story behind and the translation of the Book of Abraham. When I was studying this, I mentioned to my wife many times that I wished the church would just come clean about it, rather than try so hard to find various apologetics theories to rationalize a truth claim. The Kinderhook Plates was another brief, but catastrophic shelf breaker for me. But the shelf came crashing down when I learned about Chris and Duane Johnson's big data research into the Book of Mormon. After that, it was clear to me that Joseph Smith did not have the gift of translation, everything was a lie, and the whole church is a fraud. This is when I entered my angry phase.
It all started when I began a deeper study of Joseph Smith's revelations in the Doctrine and Covenants. I was Young Men's President at the time and our quorum had some discussion about the Word of Wisdom. I noticed a reference to "barley for all useful animals, and for mild drinks" which I had never noticed. I was curious about what a "mild drink" containing barley was and started to study the historical context surrounding this revelation, how it was interpreted and implemented early on, and how it has since evolved into a distinguishing doctrine of our faith. This process brought several questions about how the doctrines of the church can evolve and how the personal preferences of church leaders can shape our understanding of right vs. wrong. I was introduced to Dialogue and Sunstone (journals of Mormon history) and inadvertently was exposed to the story of Fanny Alger. As more questions came up, I felt I had to drill down into church history to save my faith from crumbling. I was hesitant and made it a matter of serious prayer for weeks. It was all I could think about, until I had a spiritual experience. I felt God prompting me, just like I had countless times before, to seek truth. I felt assured that if the church was true, if the restoration was real, I would find the answers and rebuild my "all-in" faith. That's when it all began to come unglued. The issues seemed never-ending. I am not sure what the final straw was that broke my shelf. I've always thought it was more the sheer magnitude of sound evidence that invalidated the whole story. Some significant shelf items for me were:
1. Book of Abraham
2. Evidence of Fraud/cover-up/sensationalizing of events in Mormon history throughout time (e.g. priesthood restoration accounts, first vision accounts, Moroni/spirit visitations, etc.).
3. Treasure digging and folk-magic culture, and how it's influence is seen in the Mormon story (Moroni, Gold Plates, Indian lore, etc.)
4. Book of Mormon issues: translation mechanics, anachronisms, 19th century sources and influence, DNA evidence, and credibility of the witnesses.
5. Kinderhook plates, Zelph, and lots in this same category.
6. Polyandry and the often gruesome details of early polygamy.
7. The evolution of church doctrine vs. culture, including race and the priesthood, Adam-God and blood atonement doctrines, the Word of Wisdom, and many others.
8. How different the story really is from how I learned and taught it. Exploring the story within the historical context is an eye-opening, but gut-wrenching, experience. So many details included in this that it's daunting to even begin to summarize.
9. How the church has adamantly controlled/denied the information until forced into transparency. This includes the church's marginalization of those willing to talk about and publish the history of the early church.
10. Many modern issues that came to light for me are :the conditional love paradigm, fear indoctrination (perpetuates the idea that it is impossible for anyone to be happy or good outside of the organization), patriarchy, LGBTQ issues, correlated curriculum, tribal shaming, all-or-none ideology, and more.
11. Etc. etc. etc. Once you get into the material it seems like there is no end.
The shelf breaking is a demoralizing, crushing experience. What hurt the most was the feeling that I had no-where to turn at first. Looking back I see the extreme cultural pressure on people to stay active, to "stay in the boat", to stay away from "anti-mormon" influences. This builds an unhealthy community of fear, judgement (of self and others), and shame for anyone who feels on the fringes. What's worse is this is the community that I had given everything to. Feeling betrayed about the control of information was hard, but feeling like the community I gave my life to had no place for me was even worse.
I was always perhaps an unorthodox member and wasn't super concerned with the letter of the law. But over time, life experiences led me to question my faith. I'd always had things on my shelf like polygamy and race, but more and more as I studied topics to examine them in order to understand them and remove them from my shelf, I ended up with more on the shelf than I started with. The church's mistreatment of outspoken members was a big part of my shelf breaking. Watching members I agreed with, like Sam Young and Bill Reel and John Dehlin face excommunication for talking about my "shelf issues" made me see the church more as a human organization bent on self preservation than The kingdom of God. Studying church history specifically around Joseph Smith also was a catalyst when I learned more about his polygamy/polyandry, scripture translation with a peep stone, multiple accounts of the first vision story, and late introductions of the first vision and priesthood restoration, along with the temple ceremonies were all devastating for my faith in the church.