During decline, demand for a good begins to taper off, and the firm may opt to discontinue the manufacture of the product. This is so, if revenue for the product comes from efficiency savings in production, over actual sales of a good/service. However, if a product services a niche market, or is complementary to another product, it may continue the manufacture of the product, despite a low level of sales/revenue being accrued. 
Digital marketing is defined by the use of numerous digital tactics and channels to connect with customers where they spend much of their time: online. From the website itself to a business's online branding assets -- digital advertising, email marketing, online brochures, and beyond -- there's a spectrum of tactics that fall under the umbrella of "digital marketing."
In the resource-based view, strategists select the strategy or competitive position that best exploits the internal resources and capabilities relative to external opportunities. Given that strategic resources represent a complex network of inter-related assets and capabilities, organisations can adopt many possible competitive positions. Although scholars debate the precise categories of competitive positions that are used, there is general agreement, within the literature, that the resource-based view is much more flexible than Porter's prescriptive approach to strategy formulation.