For Ne, the information it registers from a literal object will not be exhaustive or detailed, but be a caricature of it. Iconic qualities are emphasized while nuance is omitted, making it easier to mentally manipulate the object spatially and relationally. Two unrelated objects may be mentally associated or combined when details such as scale, shape or material are omitted; details which might make the association wholly implausible if they were considered. But by being lenient with this information, Ne succeeds in generating many more hypothetical arrangements between things than it ever could do otherwise.
Cognitive Type, ch.11
The type of Exploration Ne does is one where possibilities are generated based on a leniency toward how information can fit together. What this creates is an array of unrealistic scenarios where only the iconic qualities of objects are utilized to fit together alternate situations or scenarios --- perhaps in the direction of novelty, amusement or playfulness.
This receptiveness toward... nay, this seeking of the unrealistic is what gives Ne's hypothetical speculations a child-like quality. The association with childishness arises from how a child, due to an absence of life experience, has yet to learn the precise reasons why certain things are impractical or implausible... and as we grow, we gain a more accurate perspective of the causality of the world.
However, as Ne actively seeks these rather acausal interpretations of reality, there is a perpetually youthful element to their eyesight and imagination, despite what the Ne type's actual age may be.