A question of cost
Outcalls are actually quite a lot of hassle for the girl if you think about it.
You can easily spend 45 minutes getting ready for any call, in or out... shower, hair, make-up etc... I like to give myself an hour to get ready, although I know I can do it in under 30 minutes if necessary.
Then, once ready, you have to get to the outcall destination, leaving yourself enough time to allow for delays (nothing worse than a girl being late!) then find a way to kill some time because you invariably arrive early, and preferably find the nearest ladies loo so that you can do a last minute touch-up to your hair and make-up. And if you are going by train, as I often do if I'm doing a call in London or Gatwick, then you have to allow extra time because the trains never run precisely when you want them to. Then there is the journey home too, followed by a quick shower and change back into "normal" clothes while the kettle boils!
So you can end up spending two hours or more travelling there and back, plus the hour of preparation, which means that a 1 hour outcall is actually taking maybe 4 hours out of your day or even more.
It is damn hard to do more than 2 outcalls in a day...
Or maybe I am doing it wrong? lol....
Perhaps I should just get a taxi and do hair and make-up en route? haha.