I'd have to agree with JB.
Different types of carpet each take different amounts of time to dry. Just like being in two different climates will produce two different dry times, even on the same type of carpet.
I've had a lot of custys bitch about how long it took for the last cleaners' work to dry, and ask me how long mine will take. I always tell them that in my own home, it takes about 4 hours, and that's on the areas that are hard for air to reach. My main areas and walkpaths dry in less than 2 hours. But, I always turn my furnace fan on, set it at 72, and put my ceiling fans on, too. I always tell the custy to make sure to keep the windows open if possible, turn on any ceiling fans to push DOWN the warm air up top, and perhaps put some area fans on to help aid the drying process. They all look me right in the eyes when I say that, and they nod their heads, but I know not all of them are really LISTENING. They HEAR me, but they're not LISTENING. Big difference.
For example, I had a lady call me up a few weeks ago and said her carpet wasn't completely dry 4 hours after I left her house. I asked her if she put her furnace fan on, set it at 72, or higher if she'd like, and also put on her ceiling fans (she had 3). She said "NO, I wasn't aware I had to". DUH!! Funny how she remembers me telling her that my house dries in 4 hours, hence the reason she called me, but she couldn't remember me telling her to make sure the air kept moving until dry.
As much as I like to hear that she was less than satisfied with her last cleaner, it made me wonder 2 things. One, will she be calling me next time, or will she hold her own negligence against me? Two, if she doesn't call me, what kind of crap will she be talking about me to the next cleaner.
When you've been doing something long enough, you get to know who will be your "keepers", and who will be the one time deal. I'm not a betting man, but if I were, I'd say this lady will be a one timer. Good riddance.