A good pair of socks can last for years if you treat it well. The best socks, premium socks, and luxury socks are not disposable. They deserve a little care.
First, read the label. Cotton socks and wool socks need different temperatures. Hot water can shrink wool and break down elastic. Cold water is almost always safer.
Second, turn them inside out before washing. This protects the outside design and helps clean the inside, where sweat and skin cells collect. If the sock has a seamless toe, this also reduces friction in the wash.
Third, avoid the dryer if you can. Heat is the enemy of stretch. Designer socks and thin socks can lose shape quickly. Hang them or lay them flat.
Fourth, do not walk around in socks on rough floors. Cushioned socks can handle it for a while, but the heel and toe will wear faster.
If you buy socks on sale, check the quality first. Cheap socks are fine for some things, but a well-made pair will outlast three cheap ones. Take care of them, and they will take care of your feet.