Alcohol dulls your sense of taste and smell, so the more you drink, the less you taste. Amazing wonder of nature that works in your favor if you're not one who enjoys the taste of liquor.
When I'm mixing, sometimes I'll do that, though. Like when I make bloody marys and I start running out of V8 but still have plenty of bloody mary mix and vodka left over. Even though that's not really a drink designed to be consumed to the point of fist fighting and falling down on your forehead, I can't help it, they're just so damn delicious. Otherwise, I hate the taste of vodka.