Just goes to show happiness is 'relative'.
If last week I had paid £900 for a light pole that I had had my eye on for the last six months and was now using it and was happy with my purchase, then this week found out it was £600, my happiness could easily turn to disappointment.
If I waited until this week to buy I would be really happy that I had only paid £600 and pity those who had paid £900.
This happiness, however, could just as easily turn to disappointment if next week a newer pole that weighed only 17 grams replaced my 1700 gram 'monster'.
It's difficult to stay happy and content