The characters combine to create a powerful metaphor: a place where formidable forces (the tiger and the dragon) are currently at rest (crouching) and out of sight (hidden). It speaks to the immense potential that is not immediately apparent.
This idiom is deeply rooted in Chinese culture, particularly in the values of humility and modesty, which have Daoist and Confucian influences. Unlike the often-extroverted Western ideal of “selling yourself” or showcasing your achievements, traditional Chinese culture often respects those who possess great skill but do not boast about it (真人不露相 - “a true master doesn't show their skills”). The film *Crouching Tiger, Hidden Dragon* (2000) masterfully brought this concept to a global audience, showcasing a world of martial artists whose true, almost supernatural, abilities were concealed behind their roles as warriors, nobles, or even desert bandits. A Western concept like “a hidden gem” is similar but lacks the scale and sense of power. “A hidden gem” might refer to a great restaurant or a talented but unknown artist. 卧虎藏龙, however, implies a multitude of powerful individuals in one place. It's not just one gem; it's an entire diamond mine. It speaks to a collective environment of excellence, where anyone you meet could be a master in disguise.
卧虎藏龙 is a common and highly evocative idiom used in both formal and informal contexts. Its connotation is overwhelmingly positive, expressing admiration and awe for the depth of talent within a group or place.