When a cast comes off, the arm looks thinner and weaker. It still healed. Strength comes back with use.

Healing and strength run on two different clocks. A bone can be fully mended while the muscle around it has been quietly shrinking for six weeks, and the mirror only reports the second thing. That gap scares people into thinking the repair failed, when what is missing is simply use.

Coming back from anything, an injury or a long break, judge yourself on reps rather than on how the arm looks today. Start smaller than your pride wants, and go more often. Strength returns through repetition, not through one big test.