To put this in concrete terms, let us illustrate this point with a trivial example. Consider measuring the mass of a sample using a simple mechanical postal scale. We then infer a weight from the scale markings. We deduce the mass from a knowledge of the gravitational force. Other quantities involved like the gravitational force, the deflection distance, and the spring constant, would not be cited on line 1 for various reasons.
Deflection is a purely instrumental quantity.
It has no intrinsic relation to the weighed specimen, but only to scale design, i.e., how force is transferred to a scale reading. The spring constant is taken as a built-in constant of the instrument itself. To follow this example a little further, consider another postal scale, one that is designed with easily replaceable springs and can operate in an oven. Thus, in a thermogravimetric measurement, the materials property sought is actually derived from the signature in the behavior of the directly measured materials property. This oversimplified example may seem rather silly, but it illustrates the reasoning contributors are asked to use in composing their input to the roadmap tool.