An alternative explanation for this is that Amazon is struggling with identifying fake reviews, which could explain both why there seem to be many fake reviews and why one would get blocked from writing reviews (basically falling victim to a false positive of their fake review detection). Obviously there is also some bad UX thrown in for good measure (being able to write a review without being able to send it), but w…
Well, this bad UX has a positive consequence for Amazon, unintended or not. Products with good reviews generate more sales than those with comments stating problems with the product or delivery process, specially among infrequent buyers. (Frequent buyers may learn to ignore comments altogether, or at least spot valuable comments from fakes). So the bad pattern is not allowing fake reviews as much as it is rejecting l…
Having a cheap/free way to evaluate products by letting the customers do it is an advantage, especially if your goal is to sell everything (so you have no hope to evaluate it all yourself) – but it’s only an advantage if some useful signal is provided.
With strings of negative purchasing experiences customers might begin to look somewhere else. That’s why Amazon has a vested interest to provide reviews that are more signal than noise.