The ultimate goal is to 'maximise value retention in the communities and countries in which we invest' - in other words to get the best possible long-term value for money from the places where this company invests.

You could rearrange like this: Our objective is to maximize and retain value in local and international communities. We accomplish this by making strategic investments in areas relating to supply chain management, construction, operations and maintenance. By focusing our attention and expertise in these areas, it allows us to control costs and increase industrial capacity without compromising quality and safety.