The idea is important because currently, if you choose the wrong vocation at the age of 16, there is very little chance of you escaping your poor choices once you have matured and grown up.
For instance, I've met girls who went to work in a bank at the age of 16. By the age of 21, they realised that what they actually want to do is train to become a hairdresser or a nursery nurse or simliar.
When they apply for jobs such as "trainee hairdresser" or "assistant nursery nurse" and procure a college place to study for the NVQ required, they find that the course takes 2-3 years. Unfortunately though, their prospective employer would be forced to increase their wage to at least adult minimum wage rate just 12 months into their studies – long before they are qualified or able to perform the job they are studying for, whilst at the same time the employer still has younger, but more advanced apprentices, on the appropriate much lower apprentice rate considering their skill level.
The result of this is that businesses simply do not take on apprentices who are over the age of 19 where they can avoid it. They prefer to employ younger people for whom the government legislation does not create a conflict between the length of the course and the timing of when the pay is increased to that of a skilled worker.
This creates a massive problem for any person over the age of 19 who wishes to retrain in a new vocational trade. They are often prepared to put in the hours studying, and they accept that as an apprentice they will be forfeiting their previous levels of pay "at the bank" for a while, but they find it almost impossible to find an employer who will take them on and give them that chance, simply because they have to be paid so much more than an equivalent younger apprentice after 12 months.
If people want to retrain and accept that this means surviving on an apprentice wage until they have finished their studies, then I believe they should have the freedom to do so. The government should not prevent them doing so via red tape and legislation simply because of their age.