All digital systems are concerned with adequate timing margins.
As clock speeds in communications and semiconductors continue to increase, timing margins get even narrower. As clock frequencies increase, a parameter that has even greater impact on measurement needs is edge speed. For example, the frequency of a 500 MHz clock can easily be measured with a 1 GHz oscilloscope. What's missing is the transient and edge information. A 1 GHz scope can readily see the 200 MHz sinusoid but miss the necessary timing violation information.