Check snapback in 30 seconds

Try these steps in order

1. Place the racquet on a flat, well-lit surface and use a dry cloth to remove dirt and sweat from your hands and the stringbed. A photograph of the center on the freshly strung day provides a reference for later change. With a fingertip, move one main in the center of the contact zone about 3–5 mm sideways and release it. Repeat at points above and below, observing whether it returns immediately, returns slowly, or stays displaced.
2. Under oblique light, inspect four intersections and note whether notching is deeper in a main or a cross. Add the date and cumulative time to photographs of fraying, coating loss, and worn edges. On court, hit 15 crosscourt topspin balls with the same balls and record net clearance and first-bounce depth. Separate a stable trajectory despite slow string return from an unusual high launch despite a normal-looking stringbed.
3. If at least two of slower snapback, deep notching, and unpredictable trajectory repeat when compared with the fresh-string record, mark the setup as a candidate for restringing. Before an important match, leave enough margin instead of assuming the remaining life will be sufficient. After restringing, repeat the check to see whether snapback and on-court response actually recover. If neither changes, inspect swing, balls, and environment one variable at a time rather than blaming string condition.