Quantum theory as „physics of precision“
Classical physics lives on the illusion of mathematical exactness. However, this leads to increasing contradictions the more precise the experiments become. Thus, the atoms would have to collapse immediately, if classical physics would really be true.
It is only in these cases, when it becomes or has to be very precise, that quantum theory becomes necessary to correct the errors of classical physics.
One must always become precise when dealing with „small things“, therefore the quantum theory was discovered there, i.e. in the area of atoms.
As physics of possibilities the quantum theory predicts resulting facts only with probabilities. However, it determines the possible facts with a precision which is unthinkable in the field of classical physics.
Quantum theory “relativizes opposites”
Classical physics is about material objects that can be seen and touched. It is further about forces that cannot be seen or touched, but can be felt.
These distinctions, useful in everyday life, are relativized by quantum theory.
Thus, quantum theory reveals that quanta of matter can behave together like a quantum of force (e.g., in a superconductor, a Cooper pair of two electrons). Conversely, a quantum of force can be converted into quanta of matter (e.g., creation of an electron-positron pair from a quantum of light)
Quantum theory as physics of a „changing passage of time“
In everyday life, we experience how the passage of time as perceived by us is affected by the circumstances we face. At one time, time „flies by“, at another time it does not seem to pass at all.
The novelty of quantum theory is also evident in the fact that in a quantum system, the passage of time depends on how it is connected to its environment and how it interacts with it.
Goernitz Understanding Quantum Theory 