This post originally appeared on the Salesforce Blog. You can also read my latest Salesforce blog post, "The Hidden Influence of Excellent Customer Service."

There are a lot of myths in customer service. There's the notion that the Net Promoter Score is only about asking one question (it’s not). There’s the popular saying that the customer is always right (they aren’t). There’s even an unspoken feeling that no complaints mean things are going well (not necessarily).

Dive a little deeper and you’ll find it easy to debunk these myths. In fact, that last myth about complaints was neatly debunked in a recent post on the Salesforce blog.

There’s still one myth that persists and it’s the biggest one of all: customer service is easy.

It seems like nearly everyone believes this. Customers certainly do. They’re shocked when things go wrong, but never consider how they may have contributed to the problem. Every service failure story ever told starts with the assumption that the customer was pleasant, reasonable, and should have been easy to serve. I’m not saying customers are entirely to blame for poor service, but let’s not let them off the hook when they’re rude, unreasonable, or make an error.

Executives believe service is easy. They classically overrate their company’s ability in this area. A famous 2006 Bain study revealed that 80 percent of executives felt their companies delivered outstanding customer service. Only 8 percent of their customers agreed. (View report PDF)

Managers ascribe to this myth, too. Many fail to define great service, provide adequate training, or even bother to discuss service with their employees on a regular basis. They are so consumed with putting out fires and keeping up with an avalanche of administration that proactively developing a customer-focused team becomes a low priority.

Customer service consultants perpetuate this myth by doling out pithy advice that all sounds very common sense. They write blog posts on how to deal with angry customers in five easy steps while forgetting what it actually feels like to be yelled at by a total stranger. It seems oddly reasonable to this group that a customer service rep would absorb a profanity-laced tirade and then pull a card out of their wallet to remember the S.M.I.L.E. procedure for handling angry customers.

Many employees have bought into this myth too. There’s a phenomenon called the Dunning-Kruger effect where the less knowledgeable or skilled you are at something, the more you overrate your ability. This holds true in customer service, where the worst performers will often loudly proclaim they’re the best.

This effect is illustrated by a simple experiment I’ve repeated many times. I ask employees to rate their customer service ability on a scale of 1 – 5, with 5 being best. The average score is 4. Then, I ask them to rate the team’s customer service ability on the same scale. The average score is a 3. In other words, customer service employees consistently think they’re really good even though some of them are not.

There’s something else about the Dunning-Kruger effect that’s interesting. Everybody overestimates their ability except for one group: the very best. The best underestimate their ability. The best customer service employees never give themselves a 5 when I do my little rating experiment because they think there’s room for improvement.

That’s the secret shared by only the very best customer service employees, leaders, and companies. They know that customer service isn’t easy at all. It’s hard. They constantly worry whether they’ll be good enough and continuously try to get better.

Here are some things you’ll never hear a customer service champion say:

“We just hired a few good people and that was it.”
“All we did was send everyone to a two hour training class.”
“Our entire initiative consisted of hanging up a banner with this new slogan.”

Instead, you’ll hear:

“It starts with hiring good people.”
“Training is important, but we constantly reinforce that same message.”
“The new slogan summarizes how we go about our business every day.”

I recently asked a long-time client for advice I could share with new clients. They had improved their Net Promoter Score from 23 to 60 over a three year period. It was an impressive result and I wanted some of my new clients to be able to learn from their experience.

Without hesitation, my client said, “Tell them it’s a long process.”

That was it. I had been working with this client for three years and they still weren’t satisfied. Their exceptional improvement, glowing reputation, and stellar business results were a sign of excellent progress but not a final destination. They still worried about getting better. There was a long list of challenges to overcome and improvements to be made.

My client understood that customer service isn’t easy. It takes a real commitment.