Companies that sell online have a limited array of ways they can differentiate themselves and draw in customers. While relationships might work well in neighborhoods the customers sees price, quality and service as paradigms that are important to them. Each can be used as one method of competing online and creating a name for your brand.
Price: The ability to stay in the lower quarter quadrant of prices. Online consumers often buy at the cheapest price no matter what. Being the lowest helps you to get the "buy box" and stand out compared to the competitors. This is not possible with all products so seek to stay in the bottom quarter of all prices.
Quality: Quality is a consideration for some people who don't want things to break quickly or who plan on using materials multiple times. There is a subset of the population who wants to buy a product like a hammer to last a lifetime while others think of it as disposable.
Service: Excellent services, information, returns and repair are others ways of competing. When people are buying products they do weight return ability for cheaper items and repair/return/service for more expensive products. The more technical or mechanical the product, the more likely they will need help.