Eli5 – How are computer viruses created without destroying the creator’s computer first?

Question

I’ve always wondered how computer viruses are made. If someone creates a virus on their own computer, wouldn’t it infect and potentially destroy their system first before it’s spread to others?

In: 249

Answer 1

Virus is like a car
As long as i didnt activate it, i still be able to modify, resize, change part of said car
I could put the car on a test drive, a fake rail road that just to see if the car is functioning properly

Car = virus
Test drive = virtual computer (app that act like their own computer)