Two rooms in the same category are not interchangeable to the hotel selling them. There is an internal order in which rooms are put into service, and it explains a great deal about which door a guest ends up behind.
Occupancy is concentrated deliberately
On a quiet night, a property will fill a small number of floors rather than scattering guests across the building. Concentration is cheaper to service.
A single housekeeping section, one floor of linen runs and a shorter route for room service all follow from keeping occupied rooms close together.
The same logic lets a hotel shut down heating, cooling or lighting loads on unused floors during low season, which is a real cost rather than a rounding error.
Rooms cycle so wear spreads evenly
If a hotel always sold the same rooms first, those rooms would age at several times the rate of the rest. Carpets, mattresses and finishes would fail out of sequence.
Rotating which rooms are assigned first spreads use across the inventory so that refurbishment cycles arrive together rather than at random.
That is one reason a repeat guest asking for the same room number sometimes gets a polite deflection rather than a refusal.
Held inventory sits outside the sequence
Accessible rooms are commonly held back so they remain available for guests who need them, rather than being sold to whoever books earliest.
Connecting pairs are similarly protected, since selling one half to a solo traveler destroys the ability to sell the pair to a family.
Rooms out of order for maintenance, and a small cushion kept for problems, are removed from the sellable count entirely for the night.
Position within a category is a quiet lever
Every category contains better and worse rooms: end units, floors near elevators, exposures facing a courtyard rather than a street.
Assignment of those differences is where a front desk has discretion, and it is generally exercised toward longer stays, repeat guests and known preferences.
Since it is discretion rather than entitlement, the effective move is to state a preference clearly and early rather than to expect it automatically.
Timing changes what is available to assign
Rooms return to inventory through the day as housekeeping releases them, so the pool at eleven in the morning is a fraction of the pool at four in the afternoon.
An early arrival is choosing from whatever is already clean, which is usually the rooms vacated the previous evening rather than the best ones.
Arriving after the main check-in wave often means fewer choices again, since the desk has already assigned most of the day's inventory.