CHANGCHUN - Promotional discounts brought explosive sales for Chinese e-commerce giants during the "11-11" shopping spree that occurred on November 11, otherwise known to the Chinese as Single's Day.

But on Dec 12 ("12-12"), vendors refrained from engaging in price wars.

The companies instead promised better service, a move made in response to online shoppers' complaints regarding slow delivery and fraudulent promotions offered on Nov 11.

"The logistics for the '11-11' shopping day were intolerable, so I'm still in a quandary about whether to take the trouble this time," said Jiang Mei, a resident of Beijing.

Jiang said she waited more than 20 days to receive goods she bought on Single's Day and has lost confidence in the frequent shopping promotions offered by e-commerce firms.

China's largest e-commerce giant Alibaba took in 19.1 billion yuan ($3.04 billion) as a result of its November 11 promotions. But problems began to emerge after shoppers had emptied their wallets.

Data from the China Electronic Commerce Association showed that 8,160 complaints about online vendors were submitted in November, with 54.3 percent of the complaints targeting false consignment, promotional fraud and slow delivery on Nov 11.

E-commerce companies are subsequently paying more attention to customer communication and after-sale services during their Dec 12 shopping promotions.

Taobao, China's largest online retailer, has adopted a pricing system that allows sellers to adjust prices according to the offers they receive.

Li Bin, executive vice president of electronics retailer Suning, said the whole of December is a peak shopping season. "But there would be no price wars on Dec 12," he said.

Li said price wars do not necessarily stimulate the desire to purchase, adding that smaller companies tend to pay more attention to quality management rather than market share.

Many customers felt cheated in August after several e-commerce giants announced that they would wage large-scale price wars that later turned out to be public relations campaigns.

The fraudulent promotions damaged the reputation of the electronics retailers involved, said Zhao Ping, a researcher at the Academy of International Trade and Economic Cooperation.

Su Huiyan, an analyst at iResearch, said that given the coexistence of a large number of e-commerce firms, price wars are still effective tools in taking larger market shares.

But Cao Lei, director of the China Electronic Commerce Research Center, said e-commerce companies also need to discipline themselves to please consumers.

"Factors like offering cost-effective products and excellent services, as well as building a credible brand, determine which platforms customers decide to purchase from," said Cao.