And the fact that Chinese e-commerce giants have managed to sell more goods and service during the online shopping days in a relatively smaller domestic market than their US counterparts did in the world's biggest consumer market might indicate they do have some extraordinary commercial savvy in tapping into the pockets of Chinese consumers.

But challenges abound on both the demand side and the supply side.

For Chinese consumers to spend more online and offline, the government must work hard to deliver on the promise of doubling per capital income between 2010 and 2020 while doing its most to alleviate their worries about the costs of healthcare, education and social welfare and so on.

Equally important, China's e-commerce giants should take seriously rising consumer complaints and spare no efforts in improving their service to customers.

Though online retail accounted for only one-tenth of the country's retail sales, most complaints made by Chinese consumers last year were about online shopping. It was reported that just 58.7 percent of products sold online were found to be authentic during a random inspection in 2014 by the State Administration of Industry and Commerce.

The online retail platforms may argue about the precision and correctness of such a random inspection but they cannot turn a deaf ear to the complaints of online shoppers.

Another problem is the delayed delivery of purchases after every peak in online sales. A recent government directive requiring parcel delivery companies to obtain the personal information of senders and check the contents of their packages will only increase the challenge of timely delivering goods. The new requirement will cost efficiency but enhance the safety of deliveries, which is a key link in online shopping, but how the e-retail giants deal with such changes without undermining the satisfaction of consumers will be a key test to their ability to adapt the changing consumption environment in this country.

In this sense, every Singles Day should be a fierce competition among the e-commerce giants of how to best serve customers.

The author is a senior writer with China Daily. zhuqiwen@chinadaily.com.cn