Broken links, branded 404 pages and defensive design

Here's an email I received just now from Koss:

Hot Off The Presses!
Be the first to experience the new UR21 Koss Stereophone. Lightweight with deep bass.
Order before 8/31/05 and receive free shipping.

To take advantage of this offer:
1. Click on the link below.
2. Add UR21 to your cart.
3. Enter coupon code 081605 at checkout.

Offer expires August 31, 2005.
This offer valid in U.S. only. Not valid with other offers.

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http://www.koss.com/koss/kossweb.nsf/04ProductDetailCall?ReadForm&Home+Stereophones%5EUR21

Heck yeah, I want to be one of the first to experience the new UR21 Koss Stereophone. Here's what I got when I clicked on the link:

Looks like Koss has an amazing email promotion system. It so good, in fact, that it sends emails even before products are added to the website. Ouch...

What do you think are the chances of a typical user trying this link again and again until it works? Slim to none? I'd be willing to bet that conversion hurts for this, even if they do send another email.

And I'm not just picking on Koss here. I like their stuff, or I wouldn't ask for emails from them. The point is that, for many companies, email referrals represent a large segment of traffic to a site. Mistakes like these can be expensive, and the broken link isn't even the biggest problem. I think the biggest issue here is that Koss doesn't have a branded 404 page to keep me on the site.

Here's what I mean:
A friendly message, a link back to the home page and even some product recommendations are what make this an ideal 404 page for Amazon. It's called defensive design. And it works.

Tags: Defensive Design, 404 Pages, User Experience, Koss, Amazon