While aggressive driving or consistently slipping the clutch (if it's a manual transmission) can *contribute* to premature transmission wear over time, skipping a gear is generally a symptom of a more serious underlying problem, such as:
* Worn or damaged synchronizers: These are components within the transmission that allow for smooth gear changes. Wear and tear, or even a single hard shift, can damage them.
* Low transmission fluid: Insufficient fluid can lead to poor lubrication and gear slippage.
* Internal transmission damage: Broken gears, worn bearings, or other internal damage can cause gear skipping.
* Valve body problems: The valve body controls fluid flow within the transmission. Problems here can disrupt shifting.
* Solenoid issues (automatic): In automatic transmissions, solenoids control the movement of the shifting components. A faulty solenoid can cause shifting problems.
In short, the driver probably didn't do anything to directly *cause* the problem, but rather, the problem is likely the result of age, wear, and tear on the transmission. It needs professional diagnosis and repair.
