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Top 4 Technical Reasons Why VWO Tests Might Not Work

by Grant Merriel

Visual Website Optimizer (VWO) is the most powerful conversion testing and tracking application available, however there are a couple of issues that are outside of their control and that we, at Conversion UP, have come across. There have also been quite a few Conversion Consultants who have come to us to review a campaign they are running and help with anomalies that are occurring with their statistics. More often than not, it is one of the below items that have caused the deviation in their reporting.

However, all is not lost, as some of these issues do have some ways around them, that we have solved operationally, so we are getting these report anomalies less frequently. So, we decided to make it easy for everyone and let people know the top 4 issues that do occur quite regularly.

Disabled cookies on the visitors browser

Cookies are stored in the browser (by use of the executed JavaScript) to track the visitors assigned test and their usability. When they leave the website (for example, to purchase via ‘PayPal’ during an E-Commerce stores checkout process) and come back to the website, there is no recorded cookie from their last visit in the browser and so, the VWO software cannot see that they were previously on the site and loads a assigns them as a new test and tracks new data.

Purchasing via ‘PayPal Express’

If the customer buys with ‘PayPal Express’, they skip the ‘Checkout’ page and potentially the ‘Shopping Cart’ page. Depending on the E-Commerce platform, they might not come back to the default ‘Payment Success’ page that is being tracked by the VWO test campaign and thus, the conversion is not tracked.

Note: If PayPal is set up correctly and does send the visitor to the the ‘Payment Success’ page that is being tracked, the sale will be reported as a successful conversion but there will be an irregular amount of sale conversions, compared to shopping cart and checkout page conversions.

Slow / Intermittent Internet Connection

If a slow or intermittent internet connection is being used, some browsers can skip loading important elements, such as CSS, Images, JavaScript (which Visual Website Optimizer runs on), etc – to ensure the browser loads content that the visitors can read without waiting. This will mean that the VWO code is not loaded, therefore, the conversion test cannot be tracked and different design variants shown to the visitor.

Stopped Connection

VWO runs a JavaScript code that must be loaded for the test designs to load, the heatmaps to run and the test to be executed. This means that if a user interupts the loading of the VWO script on the website before it has been executed, their visit will not be tracked, no new designs visible, etc. Actions that could stop the connection with the website can include:

  • Clicking the ‘back’ button half way through loading
  • Clicking on a text link that has appeared before loading the entire page
  • Closing the browser during the website download

Note: Code loads from top bottom, so this can be reduced by adding third party scripts to the top of the page but in doing so, can decrease the load time of the page

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Grant Merriel

Being in the business and online space for more than 8+ years and advising to over 600+ businesses Grant has become to know a lot about conversions. When he is not working, he travels and attempts to do handstands.

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