Other times your instincts are wrong. The corpulent Santa Cruz casualty waddles in front of the crowd wearing a a Japanese flag headband; in his hand trembles a suspiciously opaque motor mug. You think, "Perhaps I should have stayed home and finished The Wire, after all." Then he shoulders some faded Les Paul, burps vodka and Dr. Pepper into the mike -- at this point you actually move toward the door -- and launches (with his neanderthal of a drummer) into a ridiculously ballsy blooze-punk blast that makes the band you came to see look like a musical mummy convention. You are so glad you didn't leave.
Lesson: the preliminary indications of a good or bad live music performance are tricky. Yet telltale signs abound. We've trolled our years of show-going experience to issue this list of 10 grave warnings. One alone may not warrant the making of an immediate exit, but should you observe two or more of these clues and choose to remain -- well, we take no responsibility for your actions thenceforth.
1. The band members' amps cost more than their braces
The whippersnappers onstage have orthodontia and full Marshall stacks -- and you're not in a middle school multipurpose room? Leave now.
2. Long Island ice teas suddenly go on special at the bar.
Nothing says "we'll all be better off if you don't remember this tomorrow" like four kinds of booze in one drink.
3. Leather pants
In 2010, only Slash, Steven Tyler, and bondage fans can get away with them.
4. Venue has a ban on large handheld signs, glitter, ecstatic screaming, or handwritten marriage proposals.
Rule does not apply if you are under the age of 14.
5. Guitarist overheard griping before the show about how "we tuned these things last week."
Although it could turn into a good laugh if he performs the first song in the wrong key.