Modern Marketers, eCommerce executives and line-of-business professionals looking to make educated decisions based on business analytics beware – Google Site Speed data has a serious bug.

Yottaa exposed a challenge with Google Analytics’ implementation of Site Speed metrics: due to the way data is sampled and averaged, Google Analytics Site Speed data can easily lead you astray because of all of the empty samples.

Yottaa recently encountered a new challenge and found that another user had recently reported the same issue.

UPDATE: (February 2, 2015) as the user cited above states, this is a sporadic issue. We have noticed that the site speed data is visible today, however, we feel it’s prudent for readers of this Blog to be aware of challenges with Segments and site speed data and to inspect any results they see.

In the previous Yottaa post, we highlighted how you can correct your Site Speed data by exporting it to Excel and cleansing it to remove zeroes. With this new issue, the moment traffic segments are adjusted, Site Speed data drops to zero across the board. Until a fix is implemented, there is literally no Site Speed data available for traffic segments (beyond “All Segments”), which makes drilling down for insights into specific channels or market segments to determine an optimization strategy impossible using Google Analytics alone. As shown in the screenshots below.

Why is this a Big Deal?

Every business with an online or mobile presence must also have a business technology strategy. As part of that strategy, Marketers and eCommerce professionals looking to make educated decisions based on business analytics will face the ongoing challenges of determining whether to leverage specialized tools or utility solutions that consolidate functionality under a single umbrella (like Google Analytics). Moreover, as the APM industry evolves, metrics and analytics will increasingly (and necessarily) be combined.

There is no shortage of performance measurement software. Online and mobile app owners can both afford to and owe it to themselves to be choosy. Relying on Site Speed data in Google Analytics is convenient, but that convenience comes at a cost. Dedicated application performance management (APM) software is purpose-built to facilitate the analysis of IT performance data. To date, there are few solutions that comingle business and IT performance analytics data successfully, if at all. Google is on the right track toward unifying a view of online and mobile app performance, but today the work you’ll do to verify your data or the mistaken conclusions you will draw as a result of misinterpreting partial data is risky business.