A hole-up area is an area where you can rest, recuperate, and get and prepare food. From all of the above mentioned, I would say that security is still your primary concern. Due to the adrenaline rush, a clear mind can easily decide what to do next (procure food or water or just rest and obviously fire is not the primary concern because smoke and light can compromise the hole-up area) and a calm environment is provided by its safety. I hope this is the answer that you were looking for.
