And this is why it’s not easy to use any of the cloud platforms parttime. They’re all full of these kinds of gotchas and your example is even a minor one since it really is quite clear from the documentation. There’s even a choice of Provisioned Throughput if you’re clicking this together in the Console, which should probably make you suspicious about what happens if you don’t use that.

But a certified AWS Architect, especially at the higher levels will easily spot the big gotchas from just your architecture diagram. Consider getting certified yourself, if you want to be more confident around these in the future. But there really is no replacement for just putting in a lot of hours.