"Millennials feel that what they value in an organization is different than the priorities of their current workplace," Aon Hewitt said. "Most employees believe their employers' current values focus on more organizational-oriented themes, including teamwork, profit and customer satisfaction.

"When asked what qualities are the most desirable in an organization, millennials cited more relationship-oriented values, including work/home balance, employee recognition, loyalty and respect. Other values with large perception gaps between current and desired include open communication, professional growth, fairness, humor/fun, clarity, and well-being (physical/emotional/mental/spiritual)."

The survey results showed considerable gaps between millennials' experiences in their current jobs in all those areas and what they had expected to find when they took the job.

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They also had plenty to say about other more concrete working conditions. Here's how they ranked areas where they would like to see improvement:

• Pay and benefits (51 percent)

• Good career or development opportunities (39 percent)

• Performance recognition (38 percent)

• Open/complete communication (34 percent)

• Flexible work environment (33 percent)

• Fun (30 percent)

• Having a strong management and leadership team (30 percent)

"Our research shows there is a clear disconnect between what millennials expect and desire from employers, and what their employers are actually offering," said Ray Baumruk, employee research leader, Aon Hewitt. "This gap is negatively impacting the engagement and retention of this generation, and may be one of the primary reasons why millennials will be looking for new opportunities in 2015."