What is the Rationale to block parking space?

I see with great interest of how some Malaysian drivers park their cars.

I see a lot of Malaysians who just like to park their cars on the road and blocking an empty parking space. They just block the parking space so other people cannot park their car in a parking bay. The irony of it is that these people don't park in the box,

Just block the empty box
Dun park in the parking box
Dun let other people park in the box
Block the traffic by parking in the middle of the road.

Why? ? ? Please tell me why? I cannot understand ! ! !
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