This refers to how the product gets to the customer; the distribution channels and intermediaries such as wholesalers and retailers who enable customers to access products or services in a convenient manner. This third P has also sometimes been called Place or Placement, referring to the channel by which a product or service is sold (e.g. online vs. retail), which geographic region or industry, to which segment (young adults, families, business people), etc. also referring to how the environment in which the product is sold in can affect sales.  4 Principles of Marketing Strategy | Brian Tracy
It's critical that your marketing department uses their understanding and analysis of your business's consumers to offer suggestions for how and where to sell your product. Perhaps they believe an ecommerce site works better than a retail location, or vice versa. Or, maybe they can offer insights into which locations would be most viable to sell your product, either nationally and internationally.
Digital Marketing Channels are systems based on the Internet that can create, accelerate, and transmit product value from producer to a consumer terminal, through digital networks. Digital marketing is facilitated by multiple Digital Marketing channels, As an advertiser one's core objective is to find channels which result in maximum two-way communication and a better overall ROI for the brand. There are multiple digital marketing channels available namely;
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. 
What does it take to do that? Simply put, you have to take a step back for a moment. You have to analyze and understand the basic mechanics of your message and how to effectively reach a larger audience without losing your shirt. The secret to all of this? No matter what marketing strategy you use, if you don't have an effective sales funnel and optimize your conversions, you'll just be throwing money away.
This includes all aspects of marketing communications; advertising, sales promotion, including promotional education, public relations, personal selling, product placement, branded entertainment, event marketing, trade shows and exhibitions. This fourth P is focused on providing a message to get a response from consumers. The message is designed to persuade or tell a story to create awareness.
Write your USP. Use the information you've gathered about your customers, products, and competition to create a unique selling proposition. This is a compelling sentence that describes the essence of your business, focusing on who you serve, what benefit you provide, and why you are the best business to provide that benefit. Your USP, also known as your value proposition, will guide all of your messaging, branding, and other marketing efforts.
Price refers to how much the company will sell the product for. When establishing a price, companies must consider the unit cost price, marketing costs, and distribution expenses. Companies must also consider the price of competing products in the marketplace and whether their proposed price point is sufficient to represent a reasonable alternative for consumers.
Market leader: The market leader dominates the market by objective measure of market share. Their overall posture is defensive because they have more to lose. Their objectives are to reinforce their prominent position through the use of PR to develop corporate image and to block competitors brand for brand, matching distribution through tactics such as the use of “fighting” brands, pre-emptive strikes, use of regulation to block competitors and even to spread rumours about competitors. Market leaders may adopt unconventional or unexpected approaches to building growth and their tactical responses are likely to include: product proliferation; diversification; multi-branding; erecting barriers to entry; vertical and horizontal integration and corporate acquisitions.