I was a bit hasty in my recent write-up about oiling firearms, and I neglected to mention a very important point. Oil is a liquid and therefore is subject to the laws of nature that effect liquids. While it is a great lubricant and protectant you have to bear in mind a few things about it. With repeated use it will wear off (common sense but funny but some people do not realize that). Less common sense, I guess because of how oil seems to cling to things, but still common sense, is that oil like other liquids can be absorbed into some things into which it comes in contact. So putting a gun that has a fine coating of oil on it into a holster results in some of the oil transferring into the holster, likewise a gun bag or whatever else is absorbent. Oil is, like other liquids, subject to the pull of gravity. This is not very noticeable when there is a fine sheen of oil on a firearms, but gravity is at work all of the time and it will cause the oil to run down sooner or later. Finally oil can and does evaporate, albeit it does take a while longer than let's say water for it to do so.
So what is the point of me telling you all of this. Well, even if you clean, then oil a firearm, and do not shoot it but instead store it in a gun case or sock, or put it in a holster and wear it everyday without shooting it, or put it in a nightstand, or put it in a gun locker - the oil will eventually either run or completely disappear. So I find it best to inspect my firearms at least quarterly, and to clean and oil them as necessary, or just reapply a bit of oil that often. This will help protect the finish of your gun, and help assure that it will operate like a well oiled machine when you need it. Also, remember that long term storage of a firearm is best accomplished not by coating it with a firearms' oil, but rather with a long term protectant made for firearms storage (but that is another story yet to come).
All the best,