Hello! One of the benefits of using the Amazon marketplace to sell its products is its huge reach, with over 200 million unique visitors to their website every month. Read carefully the reviews here
https://amazon.pissedconsumer.com/review.html and you will understand that as a seller, you gain access to millions of buyers around the world, which increases your sales potential. Plus, you can quickly upload your product listings to Amazon, which is much faster than building a traditional website.