I tried observing it once, but I don't remember what I saw. It didn't seem to be an issue so I ignored it, but I rarely encounter path-finding issues these days.
That being said, they can't function through a closed door so do your pals a favor by removing it in favour of an alternative.
You can maintain an entry-way aesthetic on your barn by...
- Building 3 high
- Attach roofing
- Destroy walls where and how you'd like your opening
Between this and ensuring adequate spacing between beds (e.g,Merchants struggle to navigate through tight bed spacing), your pals should be able to navigate perfectly fine. :)