An environment that gives a constant temperature is the most crucial factor for keeping your wine in great shape. A cave is perfect. Fluctuations in temperature can harm wine. Taking out a nice bottle for company and realizing its gone south is a disappointment, to say the least.
Too much movement, such as vibrations in a car, or lugging your wine around on long trips? Your wine doesn’t like that, either.
Strangely, wine is also picky about humidity—it does not like deserts. It seems odd, since it is in the bottle, but it’s true. (Although, the photochemical effects of sunlight and artificial light are sometimes restored when darkness returns.)
If you own some pricey wines, you might consider renting cellar space or keeping wine in a constant environment in an old-fashioned basement. Underground cellars are cool, damp and secure making them ideal.
The refrigerator? Great to chill a bottle for a few hours. Not great long-term. The refrigerator draws moisture from the cork and oxidation may occur. Putting a bottle in a bucket of ice is ideal.