The "taste" of wine is determined by dozens of factors, including type of grape, type of yeasts used, climate, soil, and storage methods. Some people shop for "good" wine simply by color ... a clean "white" or a strong "red." Did you know color is simply a matter of what type and how long the grape skins remain in contact with the grape juice during fermentation? ... all grape juice is white or clear. Others shop by "dry" vs. "sweet," meaning the level of residual sugar relative to acidity after fermentation is complete. And still others shop by region ... foreign versus domestic products ... or cost.
I think the most commonsense approach to buying wine is usage. We buy certain wines for cooking (sometimes just short of vinegar) and others to celebrate special occasions. And we don't always buy the same level of wine when having the boss over for dinner as we do when drinking alone. Hell, some of us just pull out a box of wine and go to town!
The world of wine is a land of subjectivity, full of snobs and pretenders who like to tell others what is good and why it's better than the bottle right next to it on the shelf. I have an older neighbor who has a good "winehead" on his shoulders. He once told me, "Good wine is something you try and you like, and bad wine is something you try and don't ever want to try again. Price and place and friends and family have nothing to do with it!" Good advice.