You're asking the time starved customer to generously donate time to fill in the survey for nothing in return. And asking for feedback within seconds of the customer's arrival on site may mean a quick bounce.
Calls to feedback should be treated like any other call to action - with careful attention to persuasion (copy) and usability (design and delivery).
I've come across a lot of these ForeSee surveys lately:
If you can't see the image, this is the English copy...
Thank you for visiting Best Buy Canada!
Upon leaving our website, you may be selected to take part in a customer satisfaction survey. This survey is conducted by an independent company, ForeSee Results.
The feedback obtained from this survey will help us to enhance our website. All results are strictly confidential.
...wIth 2 calls to action: "Continue" and "No Thanks"
Is this optimal? I can think of at least 3 ways to improve:
1. The copy could use a little massaging to warm it up.
"The feedback obtained from this survey will help us to enhance our website."
How about moving from company-centric to customer-centric messaging? Perhaps "Your feedback is valuable and helps us understand how we can improve your shopping experience"?
2. Calls to action need clarity.
Does "Continue" mean "Continue Shopping?" or "Yes, I'd be happy to take your survey?" I'd prefer to see clearer labeling: "Okay" and "No Thanks." A green "Okay" button and red "No Thanks" may help clarify visually.
Let's face it, most people won't even read the copy and will click a button to close. If a visitor click the wrong button in haste and receives a pop up when leaving your site, that customer is now annoyed at you and feels you have not respected his or her wishes or privacy.
3. Timing and selection.
"You may be selected" - why interrupt customers (and risk them fleeing your site in disgust) if they may not be selected? Why accost them on the first page they land on? I would recommend triggering this prompt for customers who have clicked at least 2 pages in addition to the landing page (browsing or otherwise engaging in the site). I say this as one who has opted in to several Foresee surveys (more out of analytical curiosity than altruism). Often I am faced with over 20 questions, and must select N/A for many of them because I never got far enough to look at a product image, read a description or interact with a shopping cart.
Interruptive pop ups are not the only way to listen to the "Voice of the Customer" (VOC), as Bryan Eisenberg points out there are at least 2 other methods including passive and action/behavior triggers that are worth exploring and testing.