There are lots of people who value their investment, having a card that does 10% slower, than the competition, at startand in the end does 10% better is very good for people not willing to change their cards with each new series.
Many people jump a series or two.
My GTX 465 kept me going till my GTX 760 but got quickly replaced by the 290 Vapor-x. Never had any issues with any of them, but i do hate (like most of the people) Nvidia`s Gameworks crap that blocks AMD from optimizing the drivers ... it takes time to fix stuff blindly ... and like most of the Youtube reviews pointed out Gameworks only works fine on GTX 980Ti.. the rest of the cards are usually to slow to have all those options on and have a decent frame rate anyway .. but gimping the competition is better than anything.
Nvidia trough Gameworks hurts badly the competition in GPU department and this is not good for any of us.. the users...
Dont get me wrong, it makes me quite annoyed that I spent $2k on titan blacks only to find out the new Gameworks stuff stresses the parts of my cards not considered strong (heavy tessellation is not a strength of the 7xx series, titan black is basically 780ti with 6GB of ram). That bugs me quite a bit about Nvidia's recent practices with Gameworks.
Still, I wish AMD would come anywheres near Nvidia with multi-gpu support, and that they dont irks me even more than the above situation. Maybe things are changing; they have been quite active with driver releases lately, which is unusual.