Star Wars came out of my desire to make a modern fairy tale. Fairy tales are how people learn about good and evil and how to conduct themselves in society."
- George Lucas
for The Star Wars Archives: 1977–1983 - Episodes IV-VI 40th Anniversary Edition by Paul Duncan for TASCHEN
I am really linking this series of interviews by George Lucas going with his analysis for each character in this case Anakin and Obi-Wan.
Here in Anakin´s chapter, Lucas explains Anakin´s real issue isn´t really the darkside or it´s temptations, in fact when he was a kid he already possesed many virtues related to the Jedi, he was generous, without malice, wanted to help and very compassionate despite being raised on slavery in a very horrible environment , his only issue, if you want to call it that, was that he was raised by a loving mother who he loved as well, having a family for him was something natural and neccesary and his main issue when it came to the order was that they simply didn´t work with family units, they worked in a master -apprentice relationships which were foreing to him, he had bonds with people because he was born in a family and a community. The fact he quickly could lose them given many of them were slaves only made him bond with even more intensity which translated into him having difficulty in letting go of his loved ones.
So in Lucas vision, Anakin needed a master like Qui-Gon to teach him the way of the jedi while making a transition between having a family and having a master - apprentice relationship, Qui-Gon actually WANTED to be that father figure Anakin was looking for even when he lived with his mother.
This obviously didn´t happen with Obi-Wan, who wasn´t really into the idea of being Anakin´s father figure and who wanted Anakin to adapt into the Jedi´s life as if he was raised on the temple. Lucas tells Obi-Wan´s biggest regret in both trilogies was having failed as a master for Anakin, because he didn´t adapt to Anakin´s personal needs like Qui-Gon would have done neither did he stablished many reflective opportunties over the nature or the dark and lightside like Yoda did with Luke, Obi-Wan´s teaching style was more "by the book" so in Lucas view Obi-Wan is indirectly to blame for Anakin´s fall to the darkside and the end of the republic. I think there are many attenuating circunstances about this but I could see Obi-Wan seeing it that way. Obi-Wan then begins to make similar mistakes with Luke who also gets in danger of falling like his father before him but who ultimately doesn´t fall because his training was slighty different and had Yoda´s involvement and of course because Luke himself decides to embrace compassion and value family, his bond with the father he barely knew.
Lucas mentions that he considered keeping Qui-Gon out of the story and writting obi-wan as an ambitious young Jedi who wanted to train Anakin for his intense force powers, like Obi-Wan said in the OT but he later decided to include Qui-Gon so he could be the contrast with Obi-Wan personality, the difference between Qui-Gon and Obi-Wan is one in which a man pays attention and helps a beggar(Qui-Gon) who in TPM is represented by both Jar Jar and Anakin and another man(Obi-Wan) who gets annoyed at having to deal with the beggar in the first place, which is reflected in Obi-Wan´s dialogue about "Pathetic life forms". Obi-Wan is still ambitious in TPM but not in relation to Anakin, just in the sense he´s interested in advancing his career, in fact he tells Qui-Gon he could be part of the council if he didn´t discuss so much with the council, which actually means Obi-Wan pretty much wants to be part of the Council and advance in his career as a Jedi.
I belive it was Obi-Wan´s original disconnect with Anakin, his sadness/anger over Qui-Gon wanting to end his padawanship in favor of Anakin that despite trying his best to comply with Qui-Gon´s wishes, Obi-Wan and Anakin only connected later in the story when they were both adults but they had so much conflict in their master - apprentice relationship for the way their relationship began, it wasn´t fair for Obi-Wan to teach a student he was suspiscious of because of the council pov of him but it wasn´t fair to Anakin either to have a teacher who started his training out of obligation and who thought he was dangerous, this is why this relationship ultimately failed to give Anakin the emotional and mental skills needed to use his powers adecuately and have a stronger process in his decision making to make choices for himself, having being a slave Anakin had an almost crippling difficulty to make personal decisions for himself, especially when so many people around him made decisions for him, as it stands Anakin´s one decision not prompted by somebody else in the story was to marry Padme.
Anakin having the wrong training, with many regrets over leaving his mother behind, without a father figure to lean on, then gets broken inside by his mother´s death, which leads to Vader´s persona being born inside him, Vader here represents his hate, resentment, whish for revenge over the injustice, which leads to him to attack the tusken raiders and later when he learns about Padmé dying on childbirth, he listens to the "devil"(Palpatine) who tells him he can save her for a price which was a lie.
So from Lucas pov Anakin´s fall began after his mother´s death, but wasn´t fully realized until his dreams about Padmé dying, with him being unable to do anything about it except see her die, this made him want to keep her alive at any cost but the reason for his fall wasn´t about him being particulary attracted to the darkside, or violent or evil, he simply wanted to keep the people he loved around, turning his genuine love into possessive love. He didn´t get the adecuate training for him to make the transition between having a family and being part of the Order in which attachment was forbbiden, an Order in which it was expected of him to give up his family.
The author of the video goes on to reflect how Anakin could have avoided falling if he was sent to the Temple earlier but I believe, given Luke was a lot more older than Anakin when he began his training, being raised by his mother wasn´t the problem, the problem was the training he got was the standard for a Jedi but he needed a training adapted to his particular needs as someone who came late to the temple, but the Jedi Order of the era and Obi-Wan as a teacher, the people and organization of the time in which he got to live just weren´t shaped this way.
Very interesting points by Lucas himself about Anakin´s character and then the Original trilogy is the story of how Anakin gets back from the darkside by making the opposite journey, he gets back his humanity, he gets the compassion he had by loving Luke as a father but this love didn´t become possesive the way his love for Padmé did, because Anakin/Vader were ready to give up his own life if it meant saving Luke, relearning love, compassion, he used to have as a child and getting his own balance back from the time before his mothers death.
In the interview, he compares the Jedi, the heroes of the film, to enforcers in the Mafia. Filoni has also said in the past that the Jedi would often negotiate by, essentially, placing their lightsaber on the table as an implied threat and forcing a peaceful resolution.
"Duality is also present in the characters of Obi-Wan and Qui-Gon. In the beginning, Obi-Wan is at odds with Qui-Gon, who rebels against the Jedi rules. But by the end of the film, he has become Qui-Gon by taking on his rebellious personality and his responsibilities."
- George Lucas
Star Wars - The Making of Episode I - The Phantom Menace (1999), by Laurent Bouzereau, Jody Duncan
But Obi-Wan Kenobi was not a conventional Jedi, in many ways. Although he tended to be reserved, especially when dealing with his Padawan, his former Master, Qui-Gon Jinn, had left a mark on Obi-Wan.
Star Wars - Episode II - Attack of the Clones novelization (2002)
"That's where the risk comes in. The films won't be the same; they're not made from a formula. Each is an episode in a long science fantasy epic, and those who expect to see a repeat of the first story will certainly be disappointed.
It's a big chance, but I don’t know any other way to do it."
- George Lucas interview in 2017, from The Star Wars Archives: Episodes IV-VI