Why did my package backtrack?

[Unicrone]

I live in Granada hills. I ordered a package that's coming from Canada via USPS. It arrived at the Van Nuys USPS location recently. Later as I tracked my package, it said it arrived at the Santa Clarita USPS which is a bit farther from where I live than the Van Nuys location. Why would my package go to the Santa Clarita location rather than the San Fernando location which is much close to my house than either of those USPS locations?

[WalterBlack]

The closer facility may not be set up to receive international shipments. At some point the package has to go through customs. I'm not sure if that happens at the border or closer to the destination but at some point it has to be inspected by customs.

[Unicrone]

Even if the closer facility can't accept international shipments, why did my package leave the van nuys facility to go farther from its destination?