"I were better to be eaten to death with a rust than to be scoured to nothing with perpetual motion"

This quote from William Shakespeare is a metaphor for the concept of being worn down by consistent activity. The phrase "consumed to death with a rust" is a reference to the corrosion of metal, which is brought on by a chemical reaction in between oxygen and iron. The phrase "scoured to nothing with continuous movement" is a recommendation to the idea of being worn down by continuous activity. The quote is suggesting that it is better to be used down slowly by a natural procedure than to be used down quickly by consistent activity. The quote is a caution versus the threats of overworking oneself and recommends that it is better to take breaks and rest in order to prevent being used down too rapidly. It is a pointer that it is very important to take care of oneself and to not strain oneself in order to avoid being used down too rapidly.