Many cues have a shaft more flexible than their butt that bends, springing back into shape after impact, when stick and cue ball encounter equal opposing force as Sir Issac Newton predicted. You can see a stick torque visibly when a hit is forceful with spin.
A shaft that "whips" in this manner keeps the tip on the cue ball's surface longer. Some players love this extreme flexibility, generating spin on the balls with minimal effort. Others prefer a stiff shaft. The theory is that it's easier to control direction with a cue that doesn't vibrate and throw the cue off line.
Most basic cues, priced around one hundred dollars, have a shaft flex near the middle of these two extremes. Ask your dealer about your preferences if they carry more than one brand name. They can offer you a brand of stick that feels "soft" during the shot or one that has a reputation for a "rock solid hit", mainly due to its cue shaft flex properties.
