Which good things happen to a wine if you age it? Are there any wines you should age, and some you shouldn't age?
Red wines generally benefit from aging. In the right conditions, dark and cool, tannins can smooth out removing some of their bite. Flavors can mellow and blend into something very interesting to the palette. Whites usually can follow suit, but their life span sans a few specific varieties, usually aren’t meant for aging and should be drunk young. IMO few wines are really geared for long aging, notably ports, with their high alcohol levels age well into several decades, giving the drinker unique flavors as the years go by. However, if a wine is flawed at conception, aging won’t make a purse out of a sow’s ear.