I Why do we need He in a He-Ne laser?

I've been reading about lasers. Here is what I understand so far:
We need to have population inversion, we need to have more atoms in excited state than in the ground state to achieve stimulated emission of photons. In He-Ne laser, we achieve that with Helium, it has metastable state at 20.6eV. Than, sometimes He atom collides with Ne atom and transfers its energy to Neon, excites it to about 20.6eV. At any time there are more Neon atoms in 5s than in 3p states and that gives us population inversion and a working laser.

What I don't understand is why couldn't we excite Neon atom directly, if we have electrons with energy of 20.6eV, wouldn't they do the same thing and excite Neon atom to 20.5eV and we would again have more atoms in excited state than in the ground state? Why we have to have Helium atoms transfering their energy to Neon instead of exciting Neon atom directly?

EDIT: My assumption is that Neon atom doesn't have metastable state st 20.6eV so, it wouldn't work because electrons would decay quickly into a ground state and there wouldn't be population inversion?
 
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Neon has many excited states. If you just use neon you get many different states, but not much of the excited states you want. Helium has fewer states, including one with the right energy to excite neon to a high state.
 

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