Oversized images weighing down mobile load times

Merchants love big, beautiful images on their site, the higher resolution the better. But according to research from Radware, many retailers are getting too carried away with visuals on mobile sites, and it's costing them.

The "2014 State of the Union: Mobile E-commerce Performance" report found that two out of three mobile customers expect pages to load in four seconds or less. After testing load times for the top 100 e-commerce sites, the study found that just 15 percent of full-site pages came in under that threshold with a median load time of 11 seconds, while the median time for m-dot pages settled at 4.8 seconds.

Long mobile load times are a very big deal: 30 percent of users who had a bad mobile experience never returned to the site, 33 percent opted to visit a competitor next and 65 percent said their opinion of the brand was affected.

When it comes to what's causing these sites to crawl, it seems that many have heavy images holding them back. For most pages, images are half of the page's weight, but a third of retailers aren't properly compressing them to streamline the loading process.

Many sites also aren't serving the appropriate format to different devices. Eighty-one percent automatically load m-dot versions of their site to smartphones, many which don't give shoppers full access to the site. Only 8 percent serve a tablet-optimized site to tablet users, with some even settling for a stripped down m-dot version of the site.

All of that is symptomatic of a larger problem, which is that retailers haven't entirely wrapped their heads around responsive Web design and how to get fast load times out of it.

"While it is quite possible to design a website that is both responsive and fast, these two attributes do not automatically go hand in hand," Radware said in the report. "A properly optimized responsive site requires a deep understanding and knowledge of both design and front-end performance optimization."

Retailers don't have much time to improve that understanding. The NRF estimates that 20 percent of online sales this holiday season will come from mobile, and most mobile checkout experiences aren't up to snuff. If retailers don't improve their load times, though, they may be lucky to get that far.  

For more:
-See this Radware study

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