Losing weight is a long, slow and continuous process. It is normal to lose 4 cm around the waist in 3 months. 10 days is too short. The reduction of waistline must be achieved by starvation or water reduction, and even the tightness of the ruler. No reference value.
Take your time. Lose weight, just test it once a month, and it doesn't make any sense to test it every day.