“We hit a bottleneck. The technology [AI] wasn’t mature enough yet, which means you have to combine it with a big team of people to perform manual tasks like data labeling, so you not only need to hire AI experts, professionals in the business you serve, but also a large number of workers to label data and train the machines,” he said.

https://techcrunch.com/2020/05/19/bytedance-invests-in-debt-collection-ai-company-lingxi/