What is the purpose of not delivering packages to the door when they are already in the back of the truck?

I recently ordered a computer and paid for shipping and delivery directly to my front door. I stayed home for the last two days waiting for the package to come in. I notice a Canada post truck go directly to my mailbox, but does not attempt to come to the house. They put a slip inside of my mailbox saying that they tried to reach me, but I was not home. I stopped the driver of the Canada Post truck asking where my package is.

I confronted him, saying you did not even attempt to come to the door to deliver my package. He said that he did not have my package in his vehicle, but when I demanded to see it, he opened the back of his vehicle, and lo and behold my package is sitting right there with my name on it. I have evidence that I ordered it with billing. I have an ID to show who I am yet they refuse to give me my package.

I hold him there and get on the phone with the supervisor asking why I cannot have my package delivered and the supervisor says this is what their driver was instructed to do and that I could come to their office and pick up the package once it’s dropped off there. They refused to give me my package and did not attempt to come to the door . What is the purpose of this and why do they constantly do this? This is not the first time this has happened to me and due to this being an ongoing issue, this is why I waited to see if they did in fact attempt to deliver the package or if they were lying.

UPDATE: So I went in today to pick up my computer and didn’t really have issues with that process it was busy and there was a line but overall it was fine. Staff was nice and gave me my package. I was surprised to find out that the screen that I ordered with the computer has now been returned to the sender due to a shipping address error. I was confused because both the computer and screen were ordered from the same company at the same time. I was told by the sender that both items would arrive together. I wasn’t given any detail as to cause the address error since both items were in the same order. But this is the situation I find myself in. Apparently it could be another week of me waiting before the issue with the screen gets sorted out now.