I'm learning more about digital oscilloscopes (previously have only worked on analog), and encountered a setting for trigger sensitivity, expressed as a value like 0.30 div.

Tektronix gives this description:

The oscilloscope will trigger on a signal of 0.35 divisions amplitude p-p in the range of frequencies from DC to 50 MHz. As the frequency goes beyond 50 MHz, the signal must be larger (higher in amplitude) to trigger the instrument. At 3 GHz, the signal must be at least 1.5 divisions in amplitude. Trigger sensitivity is specified with a sine wave input.

I'm confused because I thought the trigger level (the horizontal bar which selects the desired amplitude for the trigger) was a yes or no type of event. Either the waveform reaches the level or it doesn't.

The manual for the DSO I am using (a BK 2542B) doesn't explain this setting well at all: "Set the trigger sensitivity by turning the entry knob."

I'm suspicious it applies only to trigger types such as pulse and video, but sensitivity appears in the triggering menu regardless of type.