What is inherent flow characteristics in control valve?

The inherent characteristic of a valve is the characteristic published by the manufacturer, based on tests performed in a system where great care is taken to ensure that the pressure drop across the test valve is held constant at all valve openings and flow rates. The inherent characteristic, therefore, represents the relationship between valve flow capacity and valve opening when there are no system effects involved

Thank you Mr. Waqar for the question.

Here is your answer:

Inherent characteristics could be called as the ideal characteristics a control valve have in which pressure drop is least or kept constant while flow.

But practically there are some difference we find.

Or inherent characteristics could be called the characteristics of control valve checked at manufacturer's site where everything is tried to keep all certain parameters at no change or constant.