What is a common sign of mechanical wear in tools?

Abrasion and pitting on surfaces serve as a clear indication of mechanical wear in tools. This wear typically occurs due to repeated friction or contact with other materials during use. Over time, the constant grinding and stress can lead to small pits and scratches on the tool's surface, which not only affects its appearance but can also impact its effectiveness and longevity.

Rusted surfaces can indicate a lack of maintenance or exposure to moisture, but they do not directly signal mechanical wear. Bright shiny surfaces may suggest that a tool is newly polished or has been recently used, but this does not correlate with wear. Excessive lubrication often signifies an attempt to prevent wear, rather than being a sign of mechanical degradation itself. Thus, the identification of abrasion and pitting is critical for maintaining and managing tool performance effectively.