Why? And how? Electrons has to move from one energy level to another?
Until a really serious rent collector photon comes along and kicks them out entirely.And usually some time after getiing all excited with the new photon, they get tired, get rid of it and back on the couch.
Thank you, but actually, I'm not a mentor ... more like the local wise-asswhen electrons are exiced they absorb energy so they jump to a higher orbit(shell), when they go into lower shells they release energy in the form of electromagnetic waves.
When a mentor like @phinds answers a question I recommend liking his reply to show your appreciation.