There are lots of articles out there about generational differences and, as I have previously written, I think most are attributing too much to cultural or other factors. People value different things at different points in their lives, although I fully agree that younger people do have higher expectations around information access and are less concerned about hierarchy than older workers.
This article by David Lee offers some good advice for having career conversations with Gen Y employees but I think efforts would be more effective if organizations spent more time on knowledge transfer. In particular, your senior employees, especially your “experts”, know how to do a combination of tasks in certain situations or environments which are not easily taught. Organizations tend to let people absorb these skills by observing or shadowing more senior workers in a 1:1 manner over time, but it falls completely short when trying to scale your team, transfer knowledge to many people, or get folks doing things the same way.
For career purposes, especially with Gen Y employees who can find anything via search, it becomes quite frustrating to not have comparable access to clearly documented insight into how to grow their careers. As a result, people have no qualms to jump ship and go to a place which has an even incrementally better system for growing their insights. I recommend working with someone like Steve Trautman to help “double click” on your experts’ knowledge and break down their skills and knowledge into documented, teachable, testable components. This kind of specific, actionable nuggets of information can then be assigned to learn over time and becomes a motivating factor to develop and stay with the organization over time.