According to a recent blog post by Amazon, Customers complete 28% of Amazon purchases in 3 minutes or less and 50% of purchases in less than 15 minutes!
This shows the importance of your Amazon sponsored Ad being advertised on Top of Amazon Search plus rank organically well. If it takes 3 minutes or less for a customer to buy a product that means that they are not searching or scrolling for too long.
Of course also make sure that your listings are well written with good visuals to help customers get the information they are looking for quickly. There is nothing like a first impression.
But one thing to keep in mind these are overall averages, certain categories have longer exploring times