There is not a lot to say in response to the question in the title because common sense applies. When a kitten or an adult cat hides it is usually because they want to feel protected against a perceived threat, just like humans. And/or they are ill. For a kitten the former reason is more likely because they are likely to feel more insecure as they have less experience of the strange human world.
Domestic cats don’t instinctively get used to the human environment. They have to be socialised to it as they are socialized to humans and other animals. Until they feel surer of themselves and more confident, they may hide. Kittens take some confidence from a sibling who’s with them and under those circumstances I’d expect a kitten to hide less.
But being alone and tiny in a strange, unnatural land of giants it is to be expected that a kitten may have a tendency to hide at the first sign of potential threat. There is also the question of personality. Less confident kittens will obviously hide more than ones who have inherited confidence. And to be honest the human home is dangerous for kittens. They can be harmed fairly easily it seems to me. I remember an F2 Savannah kitten being trodden on and killed by a contractor who was doing work on the home of a breeder as the kittens were being raised under foot.
When I fostered my kitten, who is now my constant companion as an adult, he was 7 weeks old and he hid under the sideboard for a solid week. Yep, it is true. I left him alone more or less and eventually teased him out with prawns. He made his first steps into my world and kept on travelling. His confidence grew until he was glued to me.
More common sense is needed to deal with this understandable behaviour. Play, patience and gentleness will work wonders over time. Kittens can’t resist the opportunity to play as they instinctively want to play-hunt. And if the owner is at the other end of the cat toy, they are in the presence of their cat throughout the play session. This inevitably leads to the kitten becoming quickly socialized to the surroundings and the owner and any other person who’s present during these sessions.
It is the usual story: a calm, friendly and quiet environment combined with good play sessions and great food should quickly bring a kitten out of her shell. If not, I’d consider health issues and if in doubt see a vet. As I said cats hide when ill as they feel more vulnerable and they feel the need to protect themselves.
Kitten health is delicate. There has to be a keen awareness of the potential for diseases to developing.
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