Wall-to-wall carpet will look terrible long before it will ever wear out. The current trend is NOT wall-to-wall carpet but hard surface flooring with area rugs.

proper padding is a must to keep carpet wear at a minimum. no cheap padding!

material is the other. wool blends, woo/nylon, and the blends w/the special stain proof product.

you'll know by the price if it's a good quality! $40 sq yd is decent. $50 is really good.

Research is your best tool to be able to make a decision on price/quality comparisons and also on the content of carpeting, as that‘s important. I prefer wool (had on staircases, hallways and bedrooms) for a number of reasons and get the best underpadding you can afford, as it will have an impact on longevity. Consider adding only as a runner on stairs, if not already thinking about.

https://www.thisoldhouse.com/flooring/21017998/all-about-wall-to-wall-carpeting

What are YOUR needs? Family size? Pets? BUDGET? Wool can be difficult to maintain, especially with pets. (Trust me, I know.) Go to a reputable carpet dealer, not a big box store, and get a “lesson” on carpeting. I have found that blends with special stain proof in high traffic areas is best. And..yes, I prefer hardwood everywhere. But that is not always possible for some.

Why carpet at all? IMO a cheap way to cover crappy subfloor and not a good idea. In anew build get a flooring the same all the way through the house it makes spaces feel bigger and also makes all other decisions easier. I know people like carpet in bedrooms but IMO a nice area rug over an easy to clean floor is still a better idea.

Perhaps I should add that the majority of our house is 10” white oak flooring and we have tile in the bathrooms. The only places that we are doing carpet are the master closets, the kids’ playroom, and a secret loft in my son’s bedroom. We’re not doing wall-to-wall carpet throughout the house.