The tracking gets updated when the parcel gets scanned during transportation process. Airlines, logistics and courier services have a certain work schedule and a line for all the cargo. Sometimes the batch is getting scanned not at the moment of physical arrival to the next transport hub, but after some time, which depends on its workload. Therefore, if your tracking is not updated for a while, it means that the package is in transit or has arrived to the next transport node and is waiting for its turn.