By Charles Nicholls, Founder and CSO of SeeWhy, Inc.

Last year, 154 million people in the U.S. made online purchases amounting to $155.2 billion in sales, or approximately $1000 each, according to recent Forrester research. But these are just the ones that made it through the process: ever since the very first online purchase in 1979, significantly more people abandoned shopping carts than complete their purchases.

The shopping cart abandonment rate is currently 71 percent. That means that more than 7 out of every 10 customers that start a shopping cart process fail to complete it. And during 2009, 88 percent of U.S. online customers abandoned at least one shopping cart, or 136 million people in total.

The reasons why website visitors abandon shopping carts haven’t changed much either. A separate Forrester study shows that the cost of shipping is still the number one cause, and it has been for years. In fact, the top five causes of shopping cart abandonment are:

1. Shipping and handling costs were too high 44%

2. I was not ready to purchase the product 41%

3. I wanted to compare prices on other sites 27%

4. Product price was higher than I was willing to pay 25%

5. Just wanted to save products in my cart for later consideration 24%

Note respondents were able to give multiple answers

What’s interesting is that all of the top five reasons for abandoned shopping carts have nothing to do with the checkout process itself. These are bigger behavioral issues, related to the visitor not being ready or related to price.

Many ecommerce teams instinctively think that tuning the checkout process is the top priority when they consider increasing their website conversion rate (and reducing the shopping cart abandonment rate). In March, we polled a group of 663 ecommerce executives and online marketers and asked them what was required to have a high converting website.

The top answer given was, not surprisingly, ‘Free Shipping’ (although many ecommerce teams know that this may be very difficult to deliver), followed by ‘Guest Checkout,’ ‘Simple, Intuitive Process,’ and finally ‘Short Checkout.’ This reflects our pre-occupation with tuning shopping cart processes. In years gone by the checkout process was one of the top reasons that visitors abandoned, but as the Forrester data shows, this is now much less of a problem.

SeeWhy also conducted some research into website conversion best practices. In Lessons Learned from the Top 10 Converting Websites, we looked at what these websites do to achieve ten times higher website conversion rates than the average website conversion rates. One of the primary lessons learned was that tuning the website really isn’t all that important. In fact, only one out of the top ten sites offered a guest checkout, and most had not optimized their checkout process.

So, what the Forrester research points to is what many ecommerce teams already know: tuning the website to make the checkout process smoother is only part of the answer. In fact, many have learned that once you’ve tuned, they are still seeing high abandonment rates — perhaps reduced somewhat, but still frustratingly high.

The other area to look at is what you can do to recover abandoned shopping carts. These enable you to tackle the bigger behavioral issues: what can you do to increase the conversion rate for those customers when they are not yet ready to buy or those with an issue on price?

This is where remarketing is absolutely essential. Website visitors that have just abandoned a shopping cart are your very best prospects. After all, they almost purchased...but didn’t quite.

Something stopped them.

Experience tells us that it’s better not to try and second guess the reasons why website visitors abandon shopping carts — there are just too many potential and unique circumstances outside of your control.

What continues to amaze me is that so few currently remarket to their site visitors (16 percent of the Etail 500), despite this being so well proven as a technique in driving sales. Amazon, after all is one of the biggest proponents of remarketing, yet it is done so subtly than many don’t realize that they are being remarketed to.

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