Amazon has just changed its customer feedback link so that if everything goes perfectly, you're allowed to rate the transaction "Excellent" with just one click -- no need to add a comment.
Until recently, it didn't work that way. Even if you clicked the buttons rating the service and product as perfect, you couldn't submit the form till you also put some text in the comments box. This must have irritated thousands of people, and I was among them; eventually I wrote to Amazon pointing out that this was a real disincentive to rate sellers, and one that would disproportionately punish the best merchants -- the ones who rated just an unadorned "Excellent."
I'm sure I wasn't the only one making this point; for all I know, the campaign to revise the feedback form has been going on for years already. But it's always nice to see a huge company actually do something so small yet sensible; so often, it doesn't happen.