Earlier quoted context omitted.
Yes, this exactly. The fact that I can guarantee that my code is running, and have entire massive teams at Amazon whose literal job title is to keep my code running, it is such a freeing feeling. I might be able to delete rows from Dynamo from my code messing up, but Dynamo will never go offline.
Are you really sure?
Are you really sure that it all re-ran? No. You have to query your latest batch - which means you have to have arbitrary boundaries for when failures might have occurred like say, last 24 hours. If was a weekend, just query the whole database looking for any entry that's missing the "final" status success. Try not to run anything while you're doing this, unless your system is tolerant to the DB being locked for a full-table scan.
This is all very fragile and change-averse. Who would choose to run an ETL like this? I have worked for large companies who all end up with this rickety system. Every one, every time. God forbid you want to run tests with a mock set of serverless AWS services.