HONG KONG • Billionaire Jack Ma again encouraged tech workers to embrace the industry's extreme-overtime culture, defying a growing social media backlash.

The Alibaba Group Holding co-founder once more endorsed the sector's infamous 12-hours-a-day, six-days-a-week routine as de rigueur for passionate young workers.

In a lengthy Sunday blog post, China's richest man expanded on comments from last week, in which he dismissed people who expect a typical eight-hour office lifestyle.

"As I expected, my comments internally a few days ago about the 996 schedule caused a debate and non-stop criticism," Mr Ma wrote.

"I understand these people, and I could have said something that was 'correct'. But we don't lack people saying 'correct' things in the world today. What we lack is truthful words that make people think."

Mr Ma's earlier comments stoked a fierce ongoing debate over tales of programmers and founders dying from unrelenting stress.

Chinese tech workers protested against labour conditions on the online code-sharing community GitHub last month under the banner 996.ICU, which quickly became the site's most popular topic.

Beyond Mr Ma, several of China's most prominent industry figures have also weighed in on the controversy.

Alibaba arch-foe JD.com chief executive Richard Liu said in a recent post on his WeChat moments that, while he would never force staff to work a 996 schedule, people who slacked off were not considered his "brothers".

On Sunday, Mr Ma said forcing employees to work gruelling hours was "inhumane" - but that some wanted to do so. "Those who can stick to a 996 schedule are those who have found their passion beyond monetary gains," he wrote.

Mr Ma had made headlines last week when he told an internal meeting, Alibaba did not need people who looked forward to a typical eight-hour office lifestyle, according to a post on the company's official Weibo account. Instead, he endorsed the industry's notorious 996 work culture, that is, 9am to 9pm, six days a week.

"To be able to work 996 is a huge bliss," he said. "If you want to join Alibaba, you need to be prepared to work 12 hours a day. Otherwise why even bother joining."

The comments from Mr Ma had elicited some intense reaction.

"A load of nonsense, and didn't even mention whether the company provides overtime compensation for a 996 schedule," wrote one commenter on the Weibo post. "I hope people can stick more to the law, and not to their own reasoning."

"The bosses do 996 because they're working for themselves and their wealth is growing," another comment read. "We work 996 because we're exploited without overtime compensation."

BLOOMBERG