Yes, I am also surprised about the original author characterizing any message as helpful. I am pretty sure the "x rooms left" and similar messages can never be

Yes, I am also surprised about the original author characterizing any message as helpful. I am pretty sure the "x rooms left" and similar messages can never be really trusted. First of all hotels juggle between portals and selling locally. So they don't give all their rooms to a single portal and wait until they are sold. They add a couple of rooms to every portal and more once they are sold out. It has also happened to me (with booking.com) that a hotel had overbooked. Probably not intentionally, but they made a mistake in their juggling. Not a problem for me, they sent me to a more expensive room in a hotel 3 minutes away. So the numbers on booking.com cannot be reliable even without their direct fault. Additionally I have the strong feeling booking.com are crooks. I would not trust their numbers and messages even if they got perfect information from the hotels. I have no proof for that, but unethical practices reported above and the questionable work conditions you hear about them seem to be in line with my suspicion.