A sample household requires only one kettle. A prospective buyer will review the available options in a store and buy a model best suited to their needs. Once a kettle is selected, the rest of the available makes and models will probably be ignored for many years to come.
Furniture is similar. After some research and checking out a couch at a store to see if it’s comfy, a buyer will make a decision and then a purchase. Car shopping is the same; a buyer might have a favourite brand, but there is an expectation that such an expensive purchase will last for a long time.
These types of purchases often have tight competition, because the manufacturers and producers need to convince the buyer to choose their product, and not a product made by someone else. An opportunity to try to convince the buyer might not come again for years.
Books are more like fruit. A buyer may have certain favourites, but more often than not, they will still purchase other fruits regularly. A grocery store customer will look at the selection of fruits available and choose one that looks appealing. Price and freshness might be a factor in their decision; however, information about who grew it and where rarely make an impact. A buyer will also make fruit purchases often, in quantities higher than one, and will do so many times over the years from different suppliers.
A reader may also have favourite books, genres and authors, but, an avid reader will look outside these boundaries and pick other books as well. Purchasing one book does not prevent the reader from purchasing another one by a different author or from borrowing more books from a local library. This means that there is no real competition between authors and they can, and should, work together on honing their writing skills and strive to bring quality work to their readers.