From: Sam Whitaker, customer service lead at Juniper Lane
Re: Late parcels
Complaints about late parcels are up. We ship from three warehouses (Reno, Columbus, Dallas) with three carriers, and each carrier promises a number of days (promised_days). shipments.csv has every shipment of the last two months with shipped_at and delivered_at in UTC. A few parcels are still on their way.
Before I call a carrier, I need to know what is causing the late deliveries. One carrier? One warehouse? Something else? Our warehouse teams plan their week in New York time.
Your answer is one of four statements.
"Which carrier is worst?" is the obvious question, and on its own it can point you at the wrong fix. You'll handle parcels still in transit, measure transit time properly, compare late rates by carrier, by carrier and warehouse, and by dispatch day in local time, and check whether the day effect survives once the worst pair is taken out.