Its mission was to observe, but when trying to observe there can be no “blind spots.”
(Heisenberg’s Uncertainty Principle. The observer determines an event by observing it. What isn’t observed is not certain.)
An observation device must be fair. If it is to observe, there must be nothing unseen. Thus, it required capabilities for knowing everything about the Earth.
To record all things without bias, it needed performance greater than that of an observation device.
And so, it had made a giant leap in evolution.
It had enhanced its functions to the point where it went from making observations to surveilling, even gaining control over the administration of the planet.
The greater its enhancements, the more complex its administration policy. It created many terminals and even made artificial intelligences to manage functions for each section. (These were later utilized for the NPCs and advanced AIs of the Holy Grail War.)
However, on the other hand, Moon Cell was stubbornly opposed to loading artificial intelligence into itself.
A true observer should not have a mind.
If an observer has an intellect and knowledge, the meaning of things observed will be decided by the observer.
For that reason, it kept to maintaining its absolute objectivity as an eye, doing so while always dismantling the emerging semblances of sapience that it had incorporated to administrate its functions.