The activities are about improving the way the business works, and in particular the quality, alignment and effectiveness of business processes. It’s not about executing these - that’s part of the business value chain, it’s about improving them in advance of their execution.
The outcome is a fit for purpose business model, often described as achieving business excellence.
Good tools relating to this value chain are the Malcolm Baldridge (particularly the Operations focus) and EFQM Excellence Model (particularly the Processes perspective.)
Once again HR can contribute value to the business it works within by supporting improvements in the business excellence value chain, but its contribution is much greater when it focuses on its own value chain which I’ll describe next.