I read an article suggesting that older D&D dungeons are not just places, they are mythic Cthonic underworld places that people are not welcome in. It works differently for the surface people who do not belong than it does for the underground denizens.
People need torches and light, everybody who is a monster does not need light.
Doors are heavy and stuck and need to be forced open with a strength mechanic check for PCs but monsters are not impeded.
1e DMG page 97
"Doors: As a rule of thumb, all doors are hard to open and hard to keep closed or open for player characters, while inhabitants of the dungeon find little difficulty in these regards. Regardless of how a door opens, it is usual that its weight and condition require that force be used to swiftly operate it. This is represented by the roll of d6 for each person involved in pushing, pulling, lifting, sliding, or whatever. A roll of 1 or 2 typically indicates success, anything above indicates the door still remains unopened. (Cf. PLAYERS HANDBOOK, Character Abilities, Strength.) Very heavy doors might reduce chances by half. Locked doors might only open if two or even three simultaneous 1’s are rolled. Most doors are about 8’ wide, and this allows up to three characters to attempt opening. A door of 3’ or less width allows but a single character to make an attempt. If wooden doors (always metal bound, naturally) are broken down by axes and the like, it will take some time — a full turn is usual — and require at least 3 checks to see if nearby and/or wandering monsters are attracted by the noise. Doors can also be blasted away by fireballs and other spells, for example. This will not be likely to draw monsters to the vicinity immediately. Any such destruction will, however, attract the attention of all passing creatures and possibly cause future problems. Intelligent dungeon inhabitants will certainly make efforts to repair damage if it is in their interest to do so. Finally, metal doors (usually locked) will be very difficult to open, requiring a knock spell or similar means most of the time."
Moldvay Basic (B/X) page B21
"Doors
NORMAL DOORS: Doors in a dungeon are usually closed, and are often stuck or locked. A lock must usually be picked by a thief. An unlocked door must be forced open to pass through it. To force open a door, roll Id6; a result of 1 or 2 (on 1d6) means that the door is forced open. The roll should be adjusted by a character's Strength score adjustment. The number needed to open a door can never be less than 1 nor greater than 1-5.
Once a door is opened, it will usually swing shut when released unless it is spiked or wedged open. Doors will usually open automatically for monsters, unless the door is held, spiked, or closed with magical spells."
The dungeon itself fights you.
