The Von Neumann probe landed on Mars, surveyed the area, and deployed the initial fleet of construction bots.
The bots hastily gathered up raw materials, processed them, and then put together a shelter for the initial factory.
However, due to a bug in the system, instead of using those native raw materials to create more robots, the robots cannibalized each other to make more robots.
Well, newer generations of robots. Because their numbers kept mostly the same.
Until the materials began to wear out. Metal fatigue and oxidation caused supply issues.
The last robot rolled through the darkness, trailing sparks.