[from
here]
There was always a chance, no matter how small, that the doorways on either side of the hall would open and something unpleasant would crawl out toward them. Keeping this in mind, Sai sped up the pace even further as they moved through it. Pure paranoia didn't spur him forward as much as experience did.
The next hall over wouldn't have had any rooms for monsters to hide in, but neither did it have anywhere for them to run into should something decide to block their path. This worked both ways. It wouldn't take them long to reach the field, which was thankfully larger. However, the danger there was likely infinitely greater. Some of the more wicked creatures only showed their faces outdoors.
[to
here]