The second stage of classical magic the calculation stage not only takes the longest but is the most difficult part to do properly. To be able to perform a classical magic a magician must understand what it is they are trying to and how what it is they are trying to do works. Normally through description in a numeric sense. The more in depth a magician’s description of the desired effect the more energy efficient the magic is. This is where the step wise nature of classical magic plays a major part. Energy collection must finish before calculation can start. If calculation is not descriptive enough then all the energy collected will be wasted and the magic fail, wasting both stages of the classical magic process.
Scrolling:
The act of scrolling is the act of performing much of the calculation process for any given classical magic in advance. It takes dozens of times longer to make a scroll than it would to calculate a magic traditionally however give a classical magician a scroll the calculation step of a magic can be reduced from minutes to seconds. It only taking the user the time to fill in a number of variables into the scroll to be able to use it. Perhaps a strange set of consequences is that the simplest of classical magics when scrolled requires 23 variables in order to not be a complete failure. The time element when using a scroll gets shorter when you can judge the energy efficiency of the scroll before ever starting the energy collection process. This drastic reduction in time combined coupled with the single use nature of scrolls makes them exceptionally desirable. That said the number of individuals who are willing to put in the effort to make scrolls in comparison to their desirability is disproportionate. If counting those who are willing to actually sell scrolls this disproportionality only grows.