Hi liv and welcome!
The weight loss does seem to depend on how much you have to lose.
I was recommended to do the following:
the book suggests you can lose 10-15% of your body weight in the eight weeks. Work out what this is at the lower end (say 12%), and then divide by 8, which is what each week might be. However, you may lose slightly more at the beginning, plateau in the middle, and lose a bit more at the end.
I have not very much to lose, and have lost about 5 lbs in the 4 weeks I have been doing it, but my waist is thinner, my clothes looser, and I feel and look a bit thinner, so I think some fat is coming off my internal organs which is a very good thing.
The scales may not be your friend – weight does tend to go up and down strangely – so better to judge by clothes? Or waist measurements?
Good luck!