Author here. The reason I tend to think it's a software bug is that it seems that the system to dispatch deliveries is automated. The subcontractors get their

Author here. The reason I tend to think it's a software bug is that it seems that the system to dispatch deliveries is automated. The subcontractors get their orders from some kind of computerized system, it seems. That system seems to systematically fail to specify when they are to carry items indoors/upstairs. Whether that's due to negligence or intentional malfeasance, don't know. What I do know from experience is that there are numerous bugs on their website, besides the "unknown error" problem I've listed. It just seems like really shittily built software... So I would tend to think there's an issue with really poor software engineering practices at that company.