Rawand,
Please do not reproduce copyrighted material from the PMI. I removed hem.
EMV is an expected probability value, that's all. It it not an expense theory but a capital issue. If I invest (capital) of $100 and demand of $20 exists, my capital is a loss to -$80. If I invest $100 and demand is high with a probability of $200, my return has a potential of +$100.
The decision will always be the probability of a higher return.