> Hope you've taken the advice of making the crate into a den by draping old towels or similar, to make a darker interior.
My boy westie did the sofa-disappearing act - I gave him what I had actually bought as a travel crate, put bedding in it and towels over the top to keep the light out - he loved it. He also loved his pen .. I didn't get one until the day after I got him when I thought he seemed too overwhelmed and quiet - put it up in the living room - hey presto he went in and played like a nutcase. Loved his dark den to sleep in (although he would come out half way through the night to sprawl out for a while too). He grew out of both eventually. My girl westie - well - no dark dens for her - and she broke out of her pen and didn't want to know it after the first day - not once sought out dark corners to sleep in (though occasionally hides under a cupboard when she is muddy and hears me getting ready to wash her off - though still silly enough to come out went told too !!). BUT the funny thing is with my boy - he is 10 now - and he started seeking out darkened covered corners again like when he was a puppy - not because he is afraid of anything or timid - but I think because he is sleeping deeper now he's older and wants somewhere he can be completely undisturbed. So ... I bought a massive travel crate -put in bedding, covered over the top with a blanket to block out the light - and he's gone back to sleeping in the crate - in fact looked ecstatic when I showed him it - there was no question it was his the second he saw it - and he has taken to sleeping in there now. He even takes his toys in there like its his house (my boy has always, since the day I got him, sought out soft toys which he cuddles/paddles and sucks on the nose of (he likes teddy bears) until he goes to sleep - he has always done it and never grew out of it - and now he spends ages dragging his teddy into his crate at night after sucking on it for half an hour first).
So - to the OP - it sounds like a common thing with pups, irrelevant of breed, some seek it out dark covered corners and others seem to not need it. My boy wasn't scared or timid when he was young or at any time really - he just did it I think because he liked his own safe place.
And to the other posters (not to hijack your thread OP but) .....anyone else have their dogs seek out covered corners again years later in their senior years like my boy? I'm just intrigued if others had their's return to those ways later in life too.