Port access - why on the same side as the mouse?

There isn't a specific design reason for this placement other than convenience and ease of access for the user. It's simply a matter of where the ports are most readily accessible when using the computer.
Here's a more detailed explanation: 
Convenience:
Placing ports on the front or side of the computer case makes it easier to plug in and unplug devices like mice, keyboards, and USB drives without having to reach around to the back of the computer.
Standard Placement:
Over time, it has become a common practice to position USB ports on the front or side of a computer, making it a standard expectation for users.
Accessibility:
For users who frequently switch out devices or use multiple peripherals, having ports on the front or side is more convenient than having to access the back of the computer every time.
No Technical Requirement:
There's no technical reason why the mouse has to be plugged into a port on the same side as the mouse. It's purely a matter of user experience and ergonomics.

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