An in-universe reason for choosing Dagobah is the planet's connection to the dark side. Force-sensitive beings can feel each other's presence through the Force. Since Yoda's is such a light in the darkness, he neesd to hide in the darkest of places. Dagobah contains a dark side nexus.
Mostly, because he was testing Luke. Once he reveals himself he drops the act and becomes a lot more normal. Also, consider that Yoda was living alone on Dagobah for 22 years. That kind of isolation will make anyone a little squirrely, even a Jedi master.
Dagobah was a remote, unexplored planet in the Dagobah system, and one of the purest places in the galaxy within the Force. A remote world of swamps and forests, it served as a refuge for Jedi Grand Master Yoda during his exile after the destruction of the Jedi Order.
Yoda was not only weakened physically, but mentally and emotionally he was reeling from Order 66 and the deaths of so many Jedi. He may have had the light side of the Force with him, but at this moment it was no match for the dark side.
Dagobah is a planet brimming with the living Force in its swampy jungle, caves, and creatures. Why Yoda remained there after Order 66 may have to do either with his failure to stop Palpatine or his determination to protect the future of the Jedi at all costs.
Why Dagobah Was Driving Yoda INSANE (Extremely Dark) - Star Wars Explained
Why did Yoda refuse to train Luke?
A Jedi needs to be a selfless servant, not an aggressive warrior. Yoda's teachings were focused on balance, both literally and figuratively. He wanted Luke to gain an understanding of the Force so that he would not be consumed with the prospects of combat.
With Yoda's presence in the Force cloaked, there really wasn't any way for the Empire, Darth Vader, or Vader's Inquisitors to find the Jedi master. Another potential explanation is the planet Dagobah itself.
Thus, Yoda's bizarre way of speaking was designed to highlight what he was saying. Yet it was also designed to make sure that viewers weren't stuck reading subtitles the whole time. That way, Yoda could sound like an alien while still technically speaking English.
Though he did not directly encounter Yoda, Vader's meticulous investigation and strong understanding of the Force allowed him to deduce that if Yoda lived, Dagobah was likely where he now hid.
A duel took place in the Cave of Evil between Luke Skywalker and a vision of Darth Vader. It was part of Skywalker's Jedi training by Yoda because if he entered the cave, he could face his darkest fears.
Late into the story of Star Wars: The Clone Wars, Yoda is guided to Dagobah by the spirit of Qui-Gon Jinn. What he finds is a planet with the purest connection to the Force of anywhere he's ever been. This is the main reason why Yoda chooses this as his hiding place.
Dagobah was one of the purest planets in the galaxy, alive with the Force thanks to its abundant life. One cave in the planet's swamps roiled with the dark side. During the Clone Wars, the spirit of Qui-Gon Jinn led Yoda to this cave, where Yoda had a vision of Darth Sidious's triumph over the Jedi.
Most viewers have forgotten that Palpatine seems to have been afraid of Yoda in Star Wars: Episode III - Revenge of the Sith - and even tried to flee from their duel.
According to the events of "The Mandalorian" so far, Grogu and Yoda are not the same character. They are simply from the same species. The name of this species has never been revealed since "Star Wars" creator George Lucas wanted to give Yoda a sense of mystery.
Yoda's dark visions, including one with Anakin Skywalker, exposed his guilt over indoctrinating young Jedi and playing with their lives as toys, ultimately leading to the rise of the Sith.
Legend had it that Yoda—a Jedi who became Grand Master—was trained by N'Kata Del Gormo. A Force-sensitive Hysalrian, N'Kata Del Gormo was trained in the ways of the Force and achieved the rank of Master within the Jedi Order.
"[Yoda voice actor and puppeteer] Frank Oz told me once that Yoda speaks that way specifically in honor of his own master. That was what he had thought about it. I try to keep moving forward [with] these thoughts. And [Yaddle voice actor] Bryce [Dallas Howard] on her own made a great Yaddle.”
Star Wars Explained - A long time ago, in a galaxy far, far, away... Why didn't Yoda train Anakin Skywalker if he really thought that he was "the chosen one"? Yoda didn't want Anakin trained. He considered him to be dangerous, full of fear which could potentially be catastrophic.
Master Yoda knew that Darth Vader was once Anakin Skywalker - the boy he sensed too much fear in to train way back in Star Wars: Episode I - The Phantom Menace.
The base assumption of why Obi-Wan doesn't remember R2-D2 -- in light of the prequels -- is that Obi-Wan is feigning ignorance in A New Hope to downplay the importance of the droid's arrival. That explanation holds the most water for a number of reasons.
R2-D2 was present when Padmé gave birth to Leia and Luke, so he knew Luke was Anakin's son – but what he didn't know was that Anakin became Darth Vader. In addition to that, Anakin's fall was surely a painful event in R2-D2's life, one that he definitely wouldn't like to remember or even talk about.
