But if we apply same logic to servo systems it is difficult to analyze and develop a system to a sufficiently accurate specification.
A simple and sound definition can be sought regarding this.
Let us say we want to design a position servo control system with following specifications: The above definition is not enough to design a practical control system.
The definitions above have inherent problems with regard to what amplitude the manufacturer should take to design the servo with 10 Hz bandwidth.
This leads us to understand that giving servo bandwidth alone with no amplitude specification is almost useless.