Because Attack Speed's tooltip number always looks like it's helping, players routinely keep stacking it well past their skill's current frame breakpoint, inside a dead zone that provides exactly zero extra DPS until the next breakpoint.
See brk_frame_breakpoint_dead_zones for the mechanic and a concrete example (Rogue Puncture's 58.8%-72.49% dead zone). The trap is specifically that nothing on the UI warns you that you're in a dead zone - the stat total keeps climbing even though damage output does not.
Look up (or test) your specific skill's breakpoint table before buying more Attack Speed gear; if you're mid-dead-zone, redirect that stat budget elsewhere until you can afford to clear the next full breakpoint.
trapConfirmedAll
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