From what I've seen, packages that are marked delivered and then show up a day or two later are one of two things. Either the courier trying to falsely keep the

From what I've seen, packages that are marked delivered and then show up a day or two later are one of two things. Either the courier trying to falsely keep their on time stats and daily quotas up despite not being able to (Goodhart's law). Or a misdelivery to a neighbor who either brings it by or leaves it out so the courier informally picks it up and redelivers.