While conventional managers try to cut training time by specialising work the unintended consequence of training against demand cuts training time dramatically.
When you have thorough knowledge of customer demand, you can train new starters on handling high-frequency-predictable-value demands (things we know we are going to get a lot of).
When you do this, for example, in financial services, you cut training times from 8 weeks to 2. And people are more confident when they get on the phone.