During Final Fantasy X,
Rikku was the little girl of the group.
She was affectionate, loud, nosy,
and always had an opinion on something.
However, something that people often overlook
is that Rikku was very inexperienced in the world of Spira.
She was hesitant in certain things
and trusting people she didn't know was something
she was still getting used to.
After all, remember how she first met Tidus?
She knocked him unconscious, just in case he was a “bad-guy”.
It took her a while to finally open up to Tidus.
She didn't even start speaking English
to him until he was taken prisoner onto her ship.
It's plain to see that she was used to her own people --
trusting someone she didn't know was pretty much out of the question.
Rikku also often refused to take part in activities
and prefered to be left behind,
such as the journey through the Thunder Plains and the Farplane.
She tried to look at the bright side to life,
but as far as making changes to the darker side, she just didn't have the motivation.