People say that the elevator doesn't go all the way to the top or that someone's elevator doesn't go all the way to the top to mean that someone is stupid or mentally ill. I get the feeling his elevator doesn't go all the way to the top.
Too much mucus buildup in throat is most often due to excessive post nasal drip. This can be caused by allergies, flu, and the common cold. The phlegm that accompanies an infection can hang around long-term. It usually clears up within 4 to 6 weeks, but for some people the problem can drag on for months.
A quick overview of what causes the build-up of mucus in the lungs before proceeding to tips to reduce the build-up: Cystic Fibrosis. A hereditary disease, caused mainly due to a genetic defect that interferes with the natural production of mucus in the body.