With S3 you don't even need lambda to do something like this S3 has some setting where you can log activity on a bucket into another bucket But that setting a

With S3 you don't even need lambda to do something like this S3 has some setting where you can log activity on a bucket into another bucket But that setting allows you to set the destination bucket to be the same bucket that you're monitoring. So ~30s after something happens on the monitored bucket, S3 writes a log into the same bucket. And then that activity triggers the logging again. So every ~30-60s, forever, there's a little log written into the bucket. It takes a while to add up to something noticeable if your monthly AWS bill is already a few digits long. It's super fun to sift through the bucket a few months later when you're trying to figure out if there's any real data in the bucket or just endless logs.