The word "不良" is formed through a direct and conceptually straightforward combination of its two component characters. The first character, 不 (bù), functions as a simple negator, meaning "not". It is placed before the second character, 良 (liáng), which carries the core meaning of "good", "fine", or "virtuous". Therefore, the formation is purely ideographic and logical: the negating element directly modifies the root concept, creating the combined sense of "not good". This resultant meaning naturally extends into common applications describing anything substandard, unhealthy, or morally defective, such as in "不良习惯" (bad habits) or "不良影响" (negative influence).