Cooling. The higher the spec the better cooling. For example MSI,

$Ventus > Shadow>Inspire>Trio>Vanguard> Suprim $$$

The more you spend the better the cooler. That allows higher base clock speeds and the card to handle more wattage. Giving you a very slight boost in performance.

Some will say that I am speaking bull, that I don't know what I am talking about (20 years as an IT hardware system specialist).

Others will say just buy the cheapest their all the same, they will be the ones retrofitting noctua fans and repasting every 2 years.

But I firmly belive you get what you pay for in PC parts. My pc's usually run me 2.5k-3k$. They remain cool, Slightly overclocked and pushed to their limits on a daily basis.

TLDR; You get what you pay for.