When you give an example of things being non-greedy by default why does azzzbzzzczzz represent a document with 3 records rather than 3 documents? We intuit

When you give an example of things being non-greedy by default why does azzzbzzzczzz represent a document with 3 records rather than 3 documents? We intuitively understand why, but without defining document as special, making it consume records eagerly, or defining anchors for the start and end of the data, I think the example may be incorrect.