Recently, I wrote this article explaining why Millennials aren't getting promoted. In response to Millennial readers' requests for a deeper understanding of how being misperceived can negatively affect their careers, I'm taking it a step further and outlining exactly what's getting them fired.

Employers are seriously fed up.

To get a sense of how heated this has become, read this article by one irate employer and his prediction of the backlash that will soon ensue from the Millennials' attitudes toward work.

Additionally, this survey by SmartRecruiter of 28,000 bosses detailing where Millennials are falling short is just one example of the data to support the huge disconnect costing some Millennials their jobs. Here are the key takeaways Millennials need to know.

1. Employers don't want to be parents.

Growing up, Millennials were coached their entire lives and they unknowingly assume employers will coach them too. However, the relationship isn't the same. An employer pays us to do a job. We are service providers. Expecting extensive training and professional development to do the job doesn't make financial sense. In many employers' minds (especially, small to midsized businesses with limited budgets and resources), Millennials should foot the bill to develop themselves and make themselves worth more to the employer.

Tip: Millennials should do their best to proactively seek resources on their own to help them close gaps in skills and knowledge in the workplace. There are plenty of online tools and resources to help them put their best professional self forward. Additionally, they should seek out a mentor to privately ask questions and get guidance on how to make the right impression.

2. The anti-work attitude isn't appreciated (or tolerated).

As explained here, Millennials tend to work only the minimum time expected--and will push for flexibility and a reduced work schedule to create more time for other pursuits. Being demanding about when and how they want to do their job can be viewed as disrespectful. A great way to look at how some employers feel is the way the dysfunctional phone/cable companies work. It's annoying when they announce they can come out only on a certain day. They can't tell you what time, and then they say they'll call the day of and give you a four-hour window when they'll arrive. While the phone/cable companies have us trapped, employers don't feel the same about Millennials. They'll fire the Millennial worker and find someone who can work when they need them to--and without the attitude.

Tip: In the early days and weeks of a new job, Millennials can make up for what they lack in skills by being consistently on time. When an employer sees their commitment to their work, they will earn her trust and respect, resulting in her being comfortable with their taking time off, and even providing them with a more flexible work schedule. When Millennials prove they can deliver on their company's terms, their company will give them more of what they want.

3. Millennials' happiness isn't the employer's responsibility.

Millennials are pretty vocal about wanting work to be a "fun" place to go. Besides career development, they also desire lots of cool perks and benefits to make their job feel more rewarding. Besides nice work spaces, amenities like gym memberships, healthy meals on-site, in-house parties, etc., are being used in an effort to attract and maintain Millennial workers. Unfortunately, this is backfiring on employers--and that makes them angry. In spite of all the perks to keep them happy, Millennials are getting to these jobs and quickly showing visible signs of disappointment and dissatisfaction within months of joining the company.

Why are Millennials so tough to keep happy?

Part of the problem is how much external motivators were used on Millennials growing up. In the book Punished by Rewards, Alfie Kohn argues that Millennials have an addiction to praise, perks, and other incentives to learn--better known as bribes. Thus, when they get to the job and the newness wear off, they think it's the company's job to fix it with more incentives. But, this is where the cycle of bribing has to stop. A company can offer only so much in the form of compensation and benefits. The reality is that Millennials (like all workers) must learn to find intrinsic motivation (internal drive for work), so they can find real satisfaction and success in their careers. Since Millennials haven't learned this yet, they're experiencing sadness and confusion in the workplace. Unfortunately, their unhappiness is transparent to employers who have no desire to pay for what they perceive as a bad attitude at work.

Tip: Millennials who feel confused and unhappy in their job should not blame the employer (yet). First, they should seek some career coaching. Many Millennials just need help understanding some of the basic elements for finding an internal motivation for work. They need to know their professional strengths and workplace personas, and the defining skills they'd like to grow so they can build up their specialties and find direction and motivation at the job.

Millennials, don't get mad, get ahead!

While the rest of their peers continue to be misunderstood, smart Millennials can make some simple changes and set the standard for what an outstanding young professional looks like to employers today. As this article points out, doing so could lead an employer to fast-track a career as an example to other workers. Why not benefit from the opportunity?