^ Yup, there is a lot of superfluous junk on those written tests. And it's the Written Portion, not the Manual Portion she hasn't passed. Also, in the area she resides, North Jeolla Province, that is mostly farm, country rural area. Cars aren't as common there because the roads are mostly unpaved, dirt roads.
And you also forget that there is much more to driving and a difference between a "good" driver and a "bad" one isn't so much as not knowing the exact speed limit of highway versus local roads. There's practice, experience, and a bunch of other factors that play into ppl who are good drivers.
Ex: Someone who lives in florida their whole life may be an excellent driver in Florida's highways, local roads etc. That same driver comes up to NY where it is icy, snowing, black ice road conditions, they're driving experience and records helps, but if you've never driven in these conditions, well, you're bound to be overwhelmed because you're unfamiliar with these conditions. They may cause an accident, but does that mean they're a bad driver? No, simply no prior experience.
If she's failed so many times, then she should never be allowed on the road. Even if she gets lucky and makes the grade, she'll still be a danger on the road. She wont retain the knowledge given to her and use it to the benefit of road safety. She'll only use the knowledge long enough to pass the test and then do whatever the **** she wants.,
This is major presumption and an unfair biased one at that. Yes, I'm going to take an example from Tailspin - a Disney cartoon, but the point is to explain the inaccuracy of your presumption. Baloo is one of the best cargo pilots out there, but he nearly loses his license and plane because he can't pass the written portion; that makes him a pilot who should never be let back into the air by your reasoning.