Pettis writes extensively about China and its internal debt problem. The best primer, though lengthy, is to slog through his posts dating back to the mid-2000s.

Briefly, though: China has had artificially cheap credit in its corporate sector due to explicit government policies restricting the growth of household spending. This cheap credit caused a lot of malinvestment ("bridges to nowhere"), and there hasn't been an accounting reckoning yet.

To continue to grow, China needs its household sector to grow, both in consumption and share of the economy. This is a classic shift from middle-income to developed economy. Because right now continued growth from the corporate (generally export-driven) sector has topped out, and getting more growth out of it is costly in terms of debt.

I think those are the broad strokes. To summarize: the Beijing is responding to the explosive growth of internal debt in the economy, and the goal is to continue growing. That growth must come from the household sector, but must also include dealing with the massive debt overhang. (I suppose you could also say that Beijing's goal is to stay in power, which requires economic growth to keep the populace happy.)