Today, vocational identity often takes to establish, and most work demands very specific skills that cannot be learned except on the job.

Today, vocational identity often takes Years to establish, and most work demands very specific skills that cannot be learned except on the job.
For example, when you're learning to be a lawyer, you could easily learn all the things about laws and regulations through your book. But, you could only learn how to handle judges and read the mood of the Juries only by experiencing it over and over again