i know why. its because qui gon didnt accept his death, because when we see obi wan die, he waited to be killed look at him he is just standing there with his eyes shut not moving, when qui gon got killed unexpectedly they disappear if they accept there deaths and stay there if they dont
i thought thats why
that your theory to why they disappear is wrong
if it's about being ready to die, it shows that disappearing is just a common thing to do for jedi.
But in ANH when OB1 does it, Vader is surprised by it and even goes to check the clothes to see if it's not a visual trick.
Therefor, it is something Vader doesn't know, and since he was a jedi, he knows the "tricks". So it's something new, something that they didn't tell him and quite possibly prophecy related.
my theory is that yoda and obi wan were at one with the force when they died. yoda died while telling luke about vader and the other skywalker. obi wan sacrificed himself. plus, they were masters. qui gon was in the heat of battle. he was fighting then was like "dammit...is that a red blade in my chest?" he died suddenly and unexpectedly. as for anakin/vader, he was a jedi KNIGHT not a MASTER according to obi wan in ep.4. obi wan told luke this. i am guessing it is a trick known by experienced jedi masters, not knights or sith lords.
this is my best guess, and i am sticking to it until next year when the movie comes out.....
the propohecy is my best shot...
they don't know many things about it ... ("You believe it's this ... boy???" [insert annoyed; disgust; malcontent- smiles])
Anakin is the Chosen One... OB1 trained him, Yoda trained the one that had to redeem him and Anakin ...well, he's the exception cause he's the chosen one.
QGJ only recognised him, he never trained him
I thought that was a little weird... Clearly it's something Jedi had never done before the OT... Or Vader would've known about it
And if it had ANYTHING to do with experience, Qui-Gon would've most certainly been able to do it. If memory serves me right, he was even asked to be on the Jedi Council once or twice...