90% of the time, I am completely satisfied with Amazon. The most common issue I have is shipping, I've ordered things with free 2 day shipping that have always arrived when expected, but other things I've ordered with standard shipping, seem to sit in a warehouse somewhere until shipping time estimate arrives, causing late arrival more often than pleases me. I believe they do this to try to incentivise customers into joining Prime or paying higher rates for shipping priority. I've handled shipping and receiving duties during my career and sales that would have gone to Amazon lately, have gone elsewhere that handle S/H more the way I always did.
For a positive note, I only have received one order, in the several years I've been a customer, that didn't meet my expectations due to a missing part, but the cost of getting it on my own was less than the hassle of dealing with Amazon on the issue.