All possible that fundamental properties of the universe keep an electron in orbit at set locations in n atoms orbit.I don't think "No % of any leap" proves anything one way or another. For a start, l think there must be a strong electric (electromagnetic) field between the negative electron and the positive nucleus, also, since electrons have mass, there must be a Higgs field in the space to give them mass.
The following is a quote from the director of Fermilab. He says that the Higgs field does not impede the motion of particles.
"For example, the Higgs field is much weirder than the comparisons with molasses or crowds suggest, since it does not actually drag or impede particles, but still somehow shares its mass with them."
Article - What fills space ?;
There might be a gravitational field in that space too? Does gravity stop at the edge of an atom or does it go right through? Gravity doesn't impede motion much, the earth has been going around the sun for ~ 4.6 billion years (not sure about frame dragging though).
On top of all the above there could be other fields through that space which I don't know about. The point is that a particle being in a field need not necessarily be impeded by it.
So, for now I'm just going to stick with the statement I made in the post above and that is;
"My personal opinion is that there is nowhere in the Universe where there is absolutely nothing. I believe it's all completely filled with these mysterious quantum fields."
Of course a lot of the above is just my opinion (but not all of it ). When you say there is nothing in the space between the electron and the nucleus, is that likewise just your opinion or do you have any evidence to support that claim?
You mention fluctuation a lot in your posts, you seem to treat fluctuation as something fundamental in itself. However, fluctuation means changing or varying between different states of 'something'. So surely it is the 'something' that is fluctuating that is the most fundamental "fill thing of the universe". So, in your ideas, what is it that is fluctuating? and does this 'something' also permeate through atoms or does it stop at the edge of them?
More difficult to guess at why electrons don't degrade orbits, never loose or gain energy.
When you try to pin down the location of the electron it proves impossible.
Fluctuation IMO is just a balance act of potential energy.
Creating particles then almost instantly removing them and that is probably fine energy balance properties of fluctuation.
Before fluctuation became balanced it probably created stable particles until that energy balance was reached.
That could be a very simple reason why we now have conservation of energy.
The reason for fluctuation?
IMO either a potential energy of nothing or instability of nothing.
Everything from nothing sounds crazy but breaking down what the universe is and it's hidden amounts of nothing already it isn't a giant leap to imagine a property of nothing was the start.