1. Chidi *did* end up in the Bad Place because he drank all of that almond milk on Earth.
"So ultimately, we know that everyone (for the past 500+ years) was going to the Bad Place due to the phenomena of unintended consequences. Essentially, the act of buying an iPhone, even as a gift for grandma, was a 'bad' act because it indirectly supported child labor, lined the pockets of racist and sexist CEOs, etc. — even buying tomatoes at a supermarket was considered bad due to the economics involved. Unintended consequences threw off the algorithm, which was admittedly obsolete when it was revealed it was created when a caveman gave another caveman a gift of a rock."
"A running gag since Season 1 of The Good Place was Chidi thinking he was in the Bad Place because of buying almond milk on Earth. It was unsustainable and bad for the environment. (This was revealed long before unintended consequences, which weren't discussed until a few episodes from the finale.) Little did he know he was actually right. The unintended consequences of buying almond milk were indeed why he (and everyone in existence since 1500 AD) had been going to the Bad Place."
2. The Good Place Committee was unhelpful, useless, and pure ding-dongs on purpose.
"The Committee from the real Good Place was comically useless and never managed to take any action because its members were too busy forming committees upon committees, conducting investigations, and demoting themselves for the slightest upsets. While at first this might've seemed like a gag about how over-the-top the Good Place was, Season 4 showed another possible reason. Given the state of the Good Place with everyone as pleasure zombies and how quickly they shoved responsibility onto Michael and fled (which would seem contrary to the long lengths of time it took them to decide anything), it's possible they were deliberately impeding the efforts of the main party."
"They wanted to prevent new people getting into the Good Place or any change in the system that'd make it easier to get in because more people meant more problems they couldn't solve. They couldn't drop their 'good guy' persona and tell the truth, so they used the facade of being comically ineffectual to keep their problems from getting worse."
3. Judge Gen was smarter than she appeared and actually knew what was going to happen to each and every character by the end.
"Judge Gen was actually omniscient in the traditional sense. Chidi asked this point-blank, but while Gen didn’t say yes, she also didn’t say no. My theory is she knew more than she let on and played up the persona of a kooky, dorky aunt so she could remain impartial and instead manipulated the Soul Squad into fixing the afterlife for her. After all, the Supreme Court can’t automatically decide tomorrow that water balloons are banned — they have to hear a case about it first. Gen is just a judge, not a dictator. We noticed this in her first appearance."
"In my opinion, Gen knew the whole time everybody but Eleanor never improved enough to go to the Good Place, hence why the tests seemed to be rigged. Chidi still made a decision even if it took an hour, but pilot Chidi would never be able to do such a thing. And Tahani still had a revelation even though she opened the door to her parents. I think Gen needed to stall so Michael and Janet could come through and simply acted dumb the whole time after that."
4. The Good Place wasn't just four incredible seasons of Eleanor, Chidi, Tahani, and Jason trying to be better people. It was "Eleanor's test in the system she helped create."
"We learned that time worked differently in the afterlife (Jeremy Bearimy, baby). Events happened both before and after events took place. For argument's sake, the movie Arrival is a close parallel on how time worked in the afterlife. Even Janet mentioned she saw time differently, almost like Dr. Manhattan. With that in mind, Eleanor helped create the system from the start, went through the system, and was in the Good Place at the same Jeremy Bearimy."
"Eventually, everyone got into the Good Place, they walked through the door, and they became little voices that helped other people do good on Earth. Throughout the series, Eleanor constantly mentioned 'the little voice' in her head. After she walked through the door, she became a little voice, implying that people have been walking through the door since the beginning."
5. The dot over the "i" in the Jeremy Bearimy timeline represented a void in the afterlife, not "Tuesdays" or "the time moment when nothing never occurs."
"The scene where they talked about the Jeremy Bearimy timeline was so weird — Michael's explanation didn't make any sense. Basically, he chose the day in the week that's almost in the middle, the month that's almost in the middle of the year, and Janet added that 'it's also never.' My theory is that the dot over the 'i' in Jeremy Bearimy was actually the void of the afterlife."
6. Michael wasn't a demon disguised in a Michael suit. He was God.
"I think Michael was actually God because of the dialogue between Michael and Eleanor in the last episode, when he admitted his 'freakout' was just a ploy to get her to step up as an architect. That did it for me. Michael and his whole Good Place experience represented one of two scenarios: The first scenario might've been that heaven became overly bureaucratic and God didn't have the influence he used to. In order to correct this, Michael had to expose and bring down the point system from within, and as such, posed as a demon and helped Eleanor, Chidi, Tahani, and Jason redeem themselves."
"The second scenario might've been that the Good Place was a construct by God (aka Michael) to implement Eleanor's judgment. Her path of redemption was obvious at that point. She went way further than any of the other characters and in retrospect, the scenarios all seemed a little too custom-tailored for her growth. Because they'd been designed that way all along."
7. When Eleanor went through the door in the finale, she ended up being the "little voice in the head of that guy who went to Michael's apartment."
"I think the floating particles we saw were fragments of the good that Eleanor put into the universe. One landed on that guy and gave him a push to do the right thing and bring Michael's mail to him instead of ditching it. I do think it was a version of the little voice that Eleanor spoke of, but I love the idea that each person's little voice came from a variety of sources with Eleanor's glowing particle — and the one kind act it inspired — being only a small part of the total good in the world."
8. Chidi was in very good shape because he wanted to emulate his favorite philosophers, who were "historically jacked."
"Basically in The Good Place, we discovered Chidi was in fact jacked like a 'typical leading man in Hollywood.' This was actually more consistent with his character than it first appeared. A lot of philosophers throughout history were physically in good shape. Think of Plato (literally broad shoulders) and Leonardo da Vinci. It was quite likely Chidi had read about them and wanted to emulate them. Furthermore, it wouldn't be a stretch for Chidi to base his diet solely on this."
9. "A person's point totals depended on the consequences of their actions instead of the intentions of their actions."
"In Season 1, while Eleanor was trying to gain points in order to stay in the Good Place, her score didn't go up because her intentions were 'flawed' (she was doing kind things not to be a good person, but for the selfish reason of staying in the Good Place). But later on, we found out that no one was getting into the Good Place for a long time because everyone's actions had physical, negative consequences on other people. This further proved point totals depended on those consequences and not the intentions."
"The real reason Eleanor wasn't gaining any points in Season 1 was because the people she was trying to help weren't people — they were demons. In fact, you could see her points going up when she helped Chidi, a human. So why did she earn points when she decided to give in and go to the Bad Place?"
10. The core four were "being tortured the whole time," right up to the series finale, and were never at peace after walking through the door.
"Eleanor had to erase Chidi's mind and watch him with his ex, which was torture for her, as she broke down crying. She had to lead the team and at many points thought she was failing and had to work extra hard — she fell under immense pressure to try to save the whole universe. As for Jason, he had to watch Derek and Janet together, and Derek tried to split them apart. And then he got dumped by Janet AND was told the Jags dumped Blake Bortles. THEN, he figured out that Janet was being held hostage in the Bad Place. Chidi was obviously being tortured and Tahani was under the same pressure as Eleanor."
"They had a bizarre trial with Judge Gen and then had, like, 5 minutes to come up with an idea before Gen erased the Earth. Meanwhile, Shawn wouldn't agree to anything. They eventually came up with an idea, finally got into the Good Place, and then there was ANOTHER problem. The people in the Good Place were mindless zombies because everything was 'too good,' so then Eleanor, Chidi, Tahani, and Jason had to solve that."
"They came up with the door idea, which forced Eleanor to work harder because she was worried Chidi was going to leave and didn't want to be alone. Chidi decided to stay with Eleanor even though he knew what was going to happen to him."
11. "There was a psychic field that prevented everyone (the humans, demons, and even Janet) from thinking about the meta nature of the afterlife."
"In the very first episode, Janet said she knew everything, but the only thing she couldn't talk about was the Bad Place. I think I would have instantly asked a bazillion questions about the nature of the universe, so why didn't anyone? Did Chidi just freeze like he usually did when confronted with the same situation or did something prevent it?"
"Where did the demons come from? Who created the whole thing? Who put Shawn and Judge Gen in charge? We never knew the answers to any of those questions."
"To recap, in the Season 2 premiere, Michael forced Chidi to choose his own soulmate. Right when Chidi announced that he had chosen Angélique, Michael barged in and announced, 'We had a 4-hour time gap in your profiles on May 10, 2003.' Michael then told Chidi that his real soulmate was Pevita."
"Therefore, that was the first day Chidi tried almond milk — no amount of torture was too small. So when Michael gave Chidi the 'wrong' soulmate, he made sure it was Chidi’s fault. As we saw in Season 4, the main things Chidi wanted when he got into the afterlife were a chalkboard that anticipated your lesson flow, almond milk, and a soulmate. Michael combined two of those things into one beautiful torture."
13. And finally, Eleanor, Chidi, Tahani, and Jason were never in the Good Place or the Bad Place throughout the series. They were always "in limbo."
"They were in limbo the entire time and the whole points system, reboots, and even Shawn were all part of an ultimate test to see if they were actually going to the Good Place. The main reason why I feel this was the case was because of the extreme uncertainty of 'what will happen?' They would not have had this feeling if the Good Place architects they met were actually from the Good Place."
"While I know the architects were immortal beings, the fact that there were in fact architects should've made for less anxiety and less of an unknown."
Note: Some posts have been edited for length and/or clarity.