Does liquor ever go bad.

Yes, alcohol/liquor will go bad. Beer goes stale within an hour. A bottle of whisky will turn within a month or so.

Wow! twinkiedooter must have a very sensitive palate. Unopened beer should keep for 1-3 months. There is actually an expiration date on most beers. But I am currently drinking one that is out of date by a month and it tastes fine. Of course opened beer will go stale much faster. I should have distinguished between good beer and cheap beer. My current beer is the economical brand so they aren't that good when fresh. With a good beer it is more noticeable when they get old. (This economy has forced me to make sacrifices and trade down.)

For me liquor seems to last forever. Since I don't drink it often a bottle will last quite a while. And I have never noticed it being off. Of course I mix it with something rather than drinking it straight which might make a difference.

Wine depends on the type. Red wine keeps for years. Most people say it improves with age. White wine is best the year it was bottled. I would never buy a white over one year old. Once opened most wines spoil within a day. So I tend to buy the small 187ml bottles.