The real phenomena of Quantum Tunnelling (QT) just shows that Quantum Field (QF) forces and interactions do not obey the laws of "Classical" Physics. In QF theory, new things are happening.

You can't predict predict how an electron, for example, will behave when it encounters a barrier using Newton's Laws. The barrier might be a wall, but the interaction with the wall is definitely a Quantum Electrodynamical one.

There are two reasons for this:

1. The QF interaction is the cause, and, like I have written elsewhere, the effects are not deterministic. What happens at the barrier when an electron hits can hence only be predicted probabilistically.

2. The QF interaction does not obey Maxwell's equations.

We could describe the interaction in more detail with Quantum Electrodynamics Field theory, but we can approximate the interaction by creating a Hamiltonian based on classical dynamics (use the potential energy produced by the wall), and then plug everything into the Schrodinger ...