I have been researching products on Amazon using the Jungle Scout extension and a common thread applied throughout almost all the searches:
Price is not the dominant factor.
In many cases, the best selling product was the most expensive. The relationship between price and volume was not lower prices = higher volume but higher prices = higher volume.
Which means that people buying on Amazon were not looking for the cheapest price but other factors.
People are looking for the a product that will solve their problem and that product will put them in a better position than they were before.
I put together a quick video using the case study of two best selling products but one makes $40,000 per month profit and the other makes $3,000 per month profit on almost the same volume.
Here's the thing - they are exactly the same product.
https://youtu.be/h2geYWPOrsI