In some cases, all possible information from any angle is important, such as measurements of height, length, velocity, and probability scales for success in jumping the grand canyon with a motorcycle.
Overthinking normally is attributed to a more psychological angle.
If a young man, for instance, wants to presents a lady with flowers, and feels nervous. He might overthink the situation by imagining all possible outcomes, including her father might be a veteran suffering ptsd and would shoot him.
That would be dredging up a scenario with almost no possibility of being fact.
Overthinking situations tends to happen most often when someone hopes to talk themselves out of their own idea because of fear.