What a bright room asks you to decide first
In the evening the dark arrives on its own and the room simply is what it is, but at two in the afternoon the light becomes a decision. It is the one thing daylight guests forget to make.
Book something for eleven at night and the room has already settled itself. It is dark outside, the lamps are the only question, and choosing between the one by the bed and the one by the desk takes four seconds and no thought. Book the same thing for two in the afternoon and the room hands you a decision you have never had to make before, which is how much of the outside you want in it.
Three states, and only one of them is wrong
Curtains fully open is the state most guests default to, because they were open when the guest walked in and nobody thought about them. In a room on the fourth floor over a canal that is often fine. In a room on the second floor of a narrow street in the centre, where the building opposite is nine metres away and has windows at the same height, it is not fine, and the discovery tends to be made at the wrong moment.
Fully closed is the evening state imported into the afternoon. It works, and it is the right answer in a ground floor apartment or anywhere overlooked. What it also does is remove the one thing daylight was offering, which is a room that does not feel like a room at midnight.
Half closed is what most people land on once they have thought about it for ten seconds: the net curtain drawn, the heavy one open, or the blackout pulled to two thirds. Enough light to see by, nothing for the building opposite to look at. In a hotel that has both layers, this is the whole answer and it takes a moment.
The seasonal version of the same question
Amsterdam makes this move around the calendar in a way that catches people out. In June the light is still there at half past nine, so an eight o'clock booking is a daylight booking and the curtain question applies to it. In December it is dark by half past four, and a three o'clock booking finishes in the dark with no decision needed at all. The site talks about light rather than clock times for exactly this reason: a fixed hour means two different rooms depending on the month.
Lamps are still a question
If the curtains are closed, the afternoon becomes an evening and the lamps come back. Most hotel rooms in this city have a hard overhead light and two soft ones, and the overhead is almost never the right choice. Turn it off before she arrives rather than during, because fiddling with a light switch is a strange way to spend the first minute of an hour you have paid for.
The mirror nobody mentions
A newer hotel room often has a large mirror opposite the bed, sometimes two, and in daylight they do something a room at night does not, which is to bring the window in from the side. A room that seemed private can turn out to be reflecting the street. It takes one look from where you will actually be, rather than from the door, and if the answer is unhelpful the curtain solves it.
Why any of this is worth a note
Because it is the one preparation daylight adds and the one guests skip. The sign on the handle gets remembered because it is written about everywhere. Cash for the balance gets remembered because it is money. The curtains get forgotten because in the evening they were never a task, and a habit formed at eleven at night does not transfer to two in the afternoon.
It costs thirty seconds and it is entirely within your control, which is more than can be said for the lift, the corridor or the weather. Make the decision at one o'clock, with the room to yourself, rather than at five past two with somebody standing in it.
Apartments are a different problem
A short-let flat rarely has the two layers of curtain that a hotel room takes for granted. What it usually has instead is a single blind, a set of shutters, or nothing at all beyond a net that was put up by somebody who lives on the fourth floor and never thought about the second. In the centre, where the buildings face each other across seven or eight metres of canal street, that matters more in daylight than any hotel room ever will.
Check it the day before rather than on the day. Stand where you will actually be, look out, and see what looks back. If the answer is a kitchen window at the same height, the decision is made for you and the blind goes down. It is a thirty second job on a Tuesday and an awkward one at five past two on a Wednesday.