To answer the question in a different way, I find that employee motivation varies dramatically from person to person and generational tags have little value. When dealing with younger workers, there are a few common traits, however, and I have had some success with:
- Explaining the big picture: A lot of younger workers want to be part of something that actually produces something useful. If they think that the assigned task has no real value, then you are wasting their time and energy. When you assign something with no immediate value, make sure to explain how that work will fit in the next level.
- Ensuring a career path exists: Unfortunately, a lot of companies no longer promote from within. If you were hired as Generic Front Desk Clerk, you will remain as a clerk. If they need a new manager, they go hire a new manager. Younger workers have either experienced this directly or seen a friend work hard and get passed over so there is lower tolerance for "make work" or "scut work" tasks. If you see a future for this employee, make sure that you tell them or they will assume that you are just as bad as the rest.
- Get HR to lighten up: Flexible work schedules, telecommuting, working from a coffee shop, and a relaxed working environment are considered normal in many locations - especially the west coast of the US. Now that I've been working in a more traditional environment (Japan) for four years, I realize how soul crushing and creativity killing rigid environments can be.
Also, younger workers have no built-in loyalty to their current company. They won't "take a bullet" or give it their all just because you pay them. They can see that most companies don't actually care about them (no pension, no career path, benefit reductions, outsourcing, cost cutting, etc.) so they don't automatically care about the company. If you want them to work hard and pour their energy into the company, then you have to build trust and earn that loyalty.
I find the stereotypes of Gen X, Gen Y, and other generational tags to be inaccurate when dealing with employees. The main reason is that the majority of research easily available online (Bloomberg, CBS News, etc.) is based on interviews with students and not current workers. College campus life is quite different than the rest of the world so I rarely trust something based on student attitudes.
A study of current employees was conducted by JBA in the UK that was quoted in a couple of blogs and the results are quite a bit different. Unfortunately, the original is not readily available. There are no current articles available on PMI.org, either.