The short answer
Exercise can improve health even when the scale barely changes. Weight is shaped by food, movement, sleep, medications, health conditions and more.
Pick a better scorecard
Track something exercise directly improves: walking pace, strength, stamina, blood pressure or mood. For general health, work toward 150 minutes of moderate activity weekly plus strength work twice a week; smaller amounts still count.
If weight loss is the goal
Pair sustainable movement with food habits you can maintain. Your scale result does not decide whether the workout worked.