evolution in technology makes me feel like an idiot

one day you buy sth, say a broadband connection or a cell phone.
a week later (if not a day later) one of the following happens:
1. you can buy it half-price
2. you can buy it on the same price with extra features or peripherals or an extra gadget as a gift
3. you can buy a better device at the same price or lower

the thing is, i always have the sense that i am wasting my money or cannot get the best offer for myself, since there's always a better offer coming along a few days later. and an even better one a few days later than that. and so the story goes...