A cliche is a statement that replaces the complexity of life with the superficial self-evidence of a temporary generalisation. 

Like photography, it pretends to capture the essence of a moment, and imposes the illusion of hyper-reality, distracting attention from its own artificial framing of the situation. The very elusive nature of the expression and arrangement it captures becomes a fixed truth, and a canon to judge the many various and infinitely varied ripples of moral life that somehow bring it to mind. 

As such, as an instrument to simplify the world, it serves power and order, and is the most dangerous impediment to personal judgement and moral freedom.