On average, a satisfied customer tells three people.

But a dissatisfied one? They tell 10 people.

And those 10? They tell five.

Just like this, bad word of mouth begins to spread. Until, as this fascinating graphic from Quinntessential Marketing illustrates, 1,560 people on average hear about your customer’s bad experience … and your customer’s problem becomes your problem.

Here’s a recent example of this principle in action, forwarded to us by a reader. Brett Allcorn decides to buy a pair of $450 shoes from the designer Mark McNairy. Brett is disappointed when the shoes start to fall apart on him, so he sends an email to customer service, in which customer service tells him to not wear the shoes every day. Brett shoots back:

“Thanks. I think this should be made fully clear to customers up front.

Chalk this up as your first complaint … if you honestly think I’m the first person to care about this.

Don’t wear these shoes every day? Let’s not kid ourselves – that’s not a solution. If I pay $450 for shoes I want to wear them. The reality is that these shoes are made from low-quality material not suitable for footwear.

Stylish, but totally impractical.

I think you could solve everything by putting another durable layer at the bottom of the EVA and coating the sides with a stain-resistant coating.”

Mark responds. And hilarity ensues:

[slightly edited for language]

“Hey Brad, I think you should go f*ck yourself. If the shoes are unworn, please return them ASAP, and we will issue a full refund. I do not want assholes like you wearing my shoes.

Do you like to wear your Gucci loafers when you are pouring concrete, or running a marathon?

Congratulations! You have just won the aware for the second most annoying customer ever.

Please shop at Kenneth Cole from now on.

Best Regards,

Mark McNairy

Actually, even if the shoes are trashed, send ’em back and you shall get a full refund.

(You can view the original correspondence here).

The day Brett posted this gaffe to Facebook, eight people liked it, while 16 commented. Between that, and the Tweets, and now this blog post, many more than 10 people know about Brett’s experience.

The same thing happened in this recent thread on Penny Arcade, where a (former) customer relates his awful experience with Ocean Marketing. The Penny Arcade thread quickly spread through the blogosphere like wildfire and lead to the eventual dismissal of the marketing firm involved.

I could leave you with any number of possible lessons from these examples of customer service gone wrong. I could tell you that “the customer is always right”… to always refer to the customer by his actual name … to avoid cursing … heck, even to turn off caps lock. But, you probably know these things already.

The real point is that the internet thrives on drama. Let’s not add fuel to the fire with bad customer service.