As Dan Winterland correctly points out:
They're thrust striaght into the deep end - as if a new ATC cadet in the UK has been put stright into the approach controller's position at London Centre instsead of working his/her way up from Norwich tower. It's not the controller's fault. Blame the system that put them there, and the managers whose main aim is to save money.
At the end of the day, you get what you pay for. In this case, safety is being compromised to fulfil a budget.
Actually, it's not correct for the UK situation, at least for the first paragraph. 'Cadets' in the UK ATS provider (NATS) are put straight in to busy units after completing their basic training. It's a case of sending people from the courses to where they are needed. We don't operate a system of building people up and moving them around the country. It would be expensive and time consuming and waste a lot of time. Provision of adequate training at the unit they are posted at is the only chance these guys in the UK get to hack it at a busy unit which, more often than not, is their first posting. The vast majority of them succeed.