Up until recently, Lesson Zero was an episode that had earned itself a spot in my bottom episodes list almost since it first aired. It was the first new episode to air after I discovered (and subsequently marathoned) Friendship is Magic, so I may have had too high expectations.

Basically, my biggest gripe of the episode was also many people's favorite: Twilight's increasingly unstable mental breakdown throughout. At the time, I was horrified by Twilight actions, and strongly considered them to be out of character for her.

Would Twilight have a list to check her lists? Very likely.

Would Twilight stress out over the fact that a batch of cupcakes aren't perfect due to a tiny bit of frosting, to the point she nearly destroys them trying to make it right? Maybe, but not to this degree.

Would Twilight willingly cast a mental manipulation spell on the CMC, fully intending to get them to fight so she can save the day? ... We are still talking about Twilight, right?

Back then, I felt that the episode was a trainwreck straight through the first and second acts. It was only once Celestia showed up that the episode was saved from being an unredeemable mess. If that was the case, then what changed to make me give it a second chance?

What changed was for the last two week or so, I've been where Twilight was. I came to this realization while coming down from a panic attack.

See, regarding Twilight's mental state, many fans like to say that she has OCD or Obsessive Compulsive Disorder, because she likes everything to be neat and orderly to an almost neurotic level. Unfortunately, the need for neatness and order is only one part of OCD, yet it's the part the media focuses on the most so people assume it to be the all there it to it. Actual OCD is characterized by an onslaught of unwanted and intrusive thoughts that can range from images of self harm, to fear of contamination, to other such unfounded worst case scenarios that cause untold stress and can usually only be staved off by some form of ritual, like hand-washing or organizing things in a particular order.

As a sufferer of the disorder myself, I've had days recently where I was exactly where Twilight was during Lesson Zero: buried in stress and anxiety brought on by thoughts of impending doom unless I did everything perfectly, leading to me doing some things that, to an outside, would have looked downright crazy. To put it simply, I've been in Twilight's horseshoes.

Another factor to all this might have been the timing. Even though none of the episodes are aired in any kind of chronological order, I've heard ideas that Lesson Zero takes place not long after Return of Harmony. Considering the kind of things Twilight was put through by Discord, it may have caused a delayed reaction that would have eventually caused her anxiety to spike and worsen. What we saw was just the moment when it reached the tipping point.

Now, I still have a few gripes with the episode, namely the fact that Twilight apparently sent a Friendship report to Celestia every Tuesday for months, despite the fact that every single episode shows her writing and sending each report right after said lesson was learned, no more than hours later at most. But in terms of Twilight's actions however, I'm much more willing now to see it as actually in character for Twilight, albeit due to an untold amount of mental stress at the time.