Former Amazon Tier 2 CSA here. Generally speaking if a card is declined or does not run through there would be something in the transaction history of the order (in this case your Prime membership) on our end showing that the card failed or if the card was never tried at all. Also, if the default payment method fails the system was designed to use another one on the account automatically to avoid interruptions in Prime benefits. Thus the fine print. To put it candidly worries of overdraft fees weren’t really the concern of people who would have a payment problem with Prime but rather the interruption in service so that was prioritized.
We ran a Kai-zen on it years ago so in a sense you are correct that people in this situation represent such a small minority of customers the company wouldn’t be damaged by losing your business but as a CSA obviously no one can tell you that. But in the Kai-Zen we did toss around the idea of the customer having the option to enable an email reminder 7 days before a Prime renewal in an effort to reduce the calls we would get on the issue of Prime being charged on a card (usually due to the customer not updating their default payment method). It was implemented sometime later with a 3 day notice which would have the info the card would be charged on, e.g. your preferred payment method.
So going back to the issue of interrupted service vs overdraft inconveniences Amazon would have to put in a system that would allow you to set an option in your account on what to do in this scenario: charge another card automatically or let your benefits lapse. Personally I think this would be a great idea but sadly it’s also more that can go wrong.
I’m sure you could code in such a system no problem as could the dev team there but getting code changes, even the simplest ones takes quite some time which costs serious money especially with many of our developers making six figures a year. The problem would need happen to a significant number of people to justify the costs as well as diverting them away from higher priority projects and upgrades.
The thing is though email notices are generally sent out when there’s a payment issue… hell or even when your membership is renewed one is sent out. It’s not a perfect system however and there are times when emails are lost and do not make it out but the email notice is only seen as a courtesy and not something that should be relied on even if the customer feels otherwise.
The solution you were offered is pretty much the only one available in such a situation. Basically a “shit happens, here’s what we can do” kinda thing. If it’s determined that our system was at fault (i.e. your bank/payment processor did not send us notice that hey.. we’re declining this charge for whatever reason and the system really did just pick a random card for no good reason) then what I would have done was refund you any overdraft fees using a past order that you used the card on and issued a promotional certificate for the inconvenience. However, Amazon may have tightened up those rules by now but also peak is over at the end of January so there’s still a lot of seasonal workers taking calls and still learning what they can and cannot do.
The social media team is a level 4 position (I was level 3….doing level 4 work on the side before they outsourced our team) so the people on there are pretty much like talking to someone on the leadership team. However, unless THAT too has changed, they can’t generally give account specific info over social media. That’s a security issue at that point so I’m not really surprised they gave you the blurb treatment in this scenario.
What I would do if you still don’t have your answer how this happened, and presuming you haven’t already, I’d call in and if you get someone overseas ask to speak to someone in the US. They can transfer you and are generally more than happy to do so since they’re not paid hourly, they’re paid per contact they take. Once you have someone in the US on the line, you can ask them to check if your preferred card had any payment issues that they can see on their end or even attempted at all. If they cannot answer it then ask to speak to a member of the leadership team. You may be on hold for a bit cuz we had to get up and actually hunt one down that was free to take an escalation, avoid calling in the evening hours (Pacific time) if possible. That’s usually when we have like 1–2 leads around. Leads generally have access to more info than a CSA. Plus they can give you more current info than I can. ^_-