There’s a new Grinch in town this holiday shopping season.

Retailers’ Black Friday shopping nightmares are no longer simply overcrowded stores or running out of stock. Instead, there is a new fear to keep executives up at night in the days leading up to Thanksgiving: websites crashing.

One after another, major retailers faced tech issues as they kicked off Black Friday sales.

Shoppers on Walmart’s website dealt with technical difficulties on Wednesday evening. GameStop shoppers complained about similar tech issues on social media.

Lululemon's website crashed soon after the company kicked off its Black Friday sales on Thursday morning. Later in the day, makeup-seller Ulta's website crashed because of high traffic. UK-based brands were not immune to technical difficulties, with JD Sports and Game crashing on Thursday evening.

J Crew Black Friday

Foto: J. Crew's website crashed on Black Friday.sourceJ.Crew

Troubles continued on Black Friday. J. Crew's site encountered technical difficulties because of high demand. Lowe's site was down for many customers midday on Friday. It was difficult or impossible for Hollister shoppers to check out online. And, a deal from Cards Against Humanity drove too many people to Applebee's site, which briefly crashed.

Applebee's aside, the reason for all these crashes is straightforward: More people are shopping online on Black Friday, and they are beginning their shopping sprees earlier than ever.

Online shopping spend is expected to grow 33% compared to 2017, according to GlobalData Retail. For comparison, in-store sales are also expected to increase, but only by 1.9%.

Shoppers spent $2.4 billion online on Wednesday, a whopping 31.8% increase from 2017, according to Adobe Analytics data. Thanksgiving Day online sales hit $3.7 billion, 28% growth year over year. Black Friday is shaping up to be similarly impressive, with online sales reaching $643 million as of 10 a.m. ET, an increase of 27.8%.

While shoppers spending more is a boon for retailers, an inability to handle traffic can turn a holiday shopping dream into a nightmare.

"It's easy to go to a different site and spend their holiday money elsewhere," Bob Buffone, chief technology officer at the web-optimization software company Yottaa, told Business Inside on Thursday.

"Depending on how long the site is down, it can cost retailers a lot of money and also result in damage to the brand as shoppers take to social media to express their frustration," Buffone continued.

For example, Walmart's technical issues affected an estimated 3.6 million shoppers, according to analysis. The retail aggregator estimates that the tech problems, which lasted about 150 minutes, cost the retailer an estimated $9 million in lost sales.

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