The phrase "wearing well" implies that something is durable, long-lasting, and maintaining its quality over time. Antonyms for "wearing well" could include words such as "deteriorating," "declining," "degrading," "disintegrating," or "fading." These words suggest that something is not aging gracefully, showing signs of wear and tear, and losing its intended purpose or function. The opposite of "wearing well" could also be described as something that is "crumbling," "breaking down," "falling apart," or "flaking away." These antonyms highlight the idea that over time, everything will experience some level of wear and tear, and not all things will hold up as well as others.