NAM wroteguys why are we still comparing by performance and not by performance per dollar ?!!!!
The same reason most of us drive cars and not small 200$ motorcycles: performance per dollar is just one small factor in the grand scheme of things you also have to consider the following constraints:
1- You desktop will only fit one type of cards, and when you buy it you have to stick with it for 1 to 4 years... you won't remember in 2 years that you saved 50$ on the card, you'll only be seeing the bad performance you're stuck with(I am not judging the rx480, I'm just saying as a general case).
2- Some people have a performance goal in mind, they either want to get twice the performance they have in their current card by upgrading or they want to be able a specific game at a specific graphics setting with a minimum expected fps, and the card will either fail at that or succeed, its price is not a factor in that goal. As people are discussing, you wouldn't buy it as an upgrade for gtx970 and above.
3- in my case, I have a size constraint. My desktop only fits a 22 centimeters card and only has one six pin power connector. And since I am not willing to change my desktop yet(unless I find a buyer) and I don't want to throw more money at this desktop changing its power/case since it already swallowed a lot of money as it is, my goal is to get the absolute best 22 centimeter card to help me hold out another year or 2. So far it is looking like that card will be the evga GTX 1060