What xrundog said! Ammonia is outgassed all the time, and in the threads about Coolidors, you will find cautions to open them at least once a week (as well as any other plastic humi) as there is little or no air exchange to dissapate the ammonia, so to keep it from settleing back in the gars you open the 'dor once a week to exchange the air. Some manufacturers rush "green" cigars to market, and this exacerbates the problem, but most premium cigar houses will age their product sufficiently to ensure a smokeable gar "right out of the box".
All that being said, many cigars will benefit from aging, others may acyually go downhill! It's a subjective thing, and the only way to know, is buy a five pack of somethin, and smoke one, and let the others rest, after six months, try another, six months later, try another. If you like them alot, buy more to smoke in the meantime, but let one or two sit up. You might be plesantly surprised! if they don't improve after a year, go ahead and burn 'em. If they ever seem to be lacking, burn 'em. If they seem to be improving, buy a couple of boxes, date one and put it at the bottom of your humi, and smoke out of the other , and periodically buy another box, so when your AGED box is gone, you will have some aged cigars to replace them. This is where some of us get such ungodly quantities of cigars, is having a smokeable stash, and others that we're trying to keep our paws off of for awhile. This is just one facet of the hobby that makes it so interesting and rewarding, and if you give aging a try, I say enjoy!