I'll give you an example. All that is really required to train a basically competent lawyer can be found in the curricula of community college paralegal programs and commercial bar prep courses offered by companies like Barbri.

Training to become a lawyer should take about 1 year, and in fact, for much of US history, that's all that was required. In some situations, less than that has been required. Abraham Lincoln, for example, did not go to law school, did not apprentice, and did not take a bar exam. What he did was read Blackstone's Commentaries, alone. He was competent and successful as a lawyer.

Today, in order to become a lawyer in the United States, here's what you have to do(essentially):

1. Graduate high school or get a GED.
2. Get a four-year bachelor's degree in any subject, no matter how far removed or irrelevant to law.

3. Go to law school for three years, during which time your classes will only cover about 2/3rds or so of what is tested on bar exams. You will be taught largely in the socratic/case book method. This means that teachers will hesitate to pronounce correct concepts of law and instead will try to tease it out of students(Like Socrates with his interlocutors). They will also assign judicial opinions for you to read in order to learn law. 99% of the time, in order to glean one or two sentences of relevant information, you will have to read 5 to 10 pages of extraneous material, which the professors will also questions you about in class. You will read literally hundreds of pages a week, every week. There are books of various length, depth, and quality called "supplements" or "study guides" which are the modern day equivalent of Blackstone's Commentaries. They get straight to the point and tell you what the law is. Professors will openly mock these books, and tell you that you will flunk out of law school and never learn to think like a lawyer, and will fail the bar if you read them. Everybody relies on them heavily.

4. After you graduate, you will take a bar prep course. These are commercial prep course that last about 2.5 to 3 months. Your materials include everything that you actually need to know to pass the bar exam. I am studying from Barbri materials right now, and the condensed outline for all 18 subjects tested in my state combined is smaller than any of my casebooks from any of my classes.

5. Take and pass the bar exam. After this, you know basic legal principles in a wide range of important areas, but you aren't an expert in anything, and you were probably also never taught basic practical skills, like where to file a complaint(as in physically, where the courthouse is and what room to go to) or how to set up a client trust fund account so you don't inadvertently commit grave malpractice.

There's a conservative judge named Richard Posner, who, among many other people, have pointed out that legal education is essentially a medieval guild system intended to keep people out of the profession in order to maintain the livelihood of the people in the profession. That's the real goal.