How regularly do you have your obese clients weigh themselves?
I have my clients weigh in once a week using an electrical impedance scale that measure both their weight and bodyfat percent. I of course also have them measure their waist, hips, thighs, neck & upper arms every 6 weeks.
Remember, the client realyy wants to lose bodyfat, not just weight, and if being trained properly will understand that even if their weight does not drop for a week or two, their bodyfat percent should.
The most important thing is don’t let them become discouraged by a plateau and go into self-sabotage mode where they just give up!