It's not easy being green. But the lesson in this story is that it's harder still when you're easily replaceable and you haven't negotiated a good contract.

My colleague Justin Bariso told the story of what happened to Steve Whitmire, the man who has provided the voice for Kermit the Frog for 26 years--since the death of Jim Henson in 1990. Last year, it's now being reported, Disney fired Whitmire, and as Bariso points out there's a major lesson in emotional intelligence to be learned from his story.

But buried in the New York Times story that broke all this to begin with, there's a one-sentence quote from Whitmire that contains another incredibly important moral:

"The only thing I've done my whole adult life, and it's just been taken away from me."

I have no idea who is in the right and who is in the wrong in the Disney-Whitmire dispute. But it's hard to garner any special level of sympathy for Whitmire. Stories like his are told every day in America--people who dedicated themselves to their work only to see it disappear. The difference is that they're unknown, and they don't get written up in the New York Times or Inc.com.

According to the Times, Whitmire joined Henson's team on "The Muppet Show" when he as only 19, back in 1978. Before taking over as the voice of Kermit, he was already voicing a lot of other beloved characters. He truly does seem to have dedicated himself to the brand, and it's unclear whether he became wealthy as a result of his work.

Regardless, there are at least five crucial things to take away from his story, and his one-sentence summary.

1. Don't let others define your worth.

The saddest part about Whitmire's sentence isn't what happened to him. It's how he's reacted to it and apparently sees himself. Separately he calls voicing Kermit his "life's work." Yes, Kermit is what he's best known for, but it's his choice to define himself this way.

2. Own your creativity.

Whitmire didn't create Kermit or any of the Muppets characters. He voiced them--and let's be fair, until the story of his firing came about, only the most die-hard fans had heard of him. It's not clear from anything I can find whether Whitmire tried to create anything outside of his Muppets work. And as a result, his employer owned everything.

3. Diversify, diversify, diversify.

Check out Whitmire's IMDB page. It goes on forever--but every single entry has to do with the Muppets. It's not clear that he voiced a commercial, for example, or did anything to diversify his career. Granted, it's possible he had a noncompete clause in his contract with Henson or Disney--but if so, he should have understood the career risk.

4. Learn the business side.

Whitmire is a puppeteer and voice actor, going head to head with one of the biggest brands in entertainment--and yet it's not clear he even had a lawyer or an agent advocating on his behalf. Based on the new coverage coming out, there's no indication that he worked to understand how the business actually worked-and that came back to bite him.

5. Learn to negotiate.

A lot of the lessons above ultimately come down to being able to stand up and negotiate for yourself. If that's way outside your comfort zone, or the issues are likely to become emotional for you, then the lesson is to hire someone else to do the negotiating for you. Otherwise you're likely to sign a one-sided deal. And guess whose side it will always favor?