Why does prospect theory suggest that investors are inconsistent in their attitude to risk?

Prospect theory explains that investors evaluate outcomes relative to a reference point, often the purchase price or a recent portfolio value, rather than focusing solely on final wealth. The value function is typically described as loss averse, meaning losses hurt more than equivalent gains feel good. This creates inconsistent risk attitudes: investors often become risk seeking when facing losses and risk averse when sitting on gains. A practical expression of this is the disposition effect: investors tend to hold losing positions too long to avoid crystallising a loss, while they take profits too quickly to lock in gains and feel the satisfaction of being right. That behaviour is inconsistent because the risk decision changes depending on whether the investor is in a gain or loss position, even when the underlying prospects of the investment have not improved. CISI-style questions usually test this exact pattern: reluctance to realise losses combined with a tendency to realise gains early, driven by loss aversion and reference dependence.