Taking into consideration the long distance carriers serving your area, do you know where all the fibers cross your route and have you made provisions for potentially connecting to them in the future? Tying your network to long distance carriers' fiber may increase the potential revenues you can realize from dark fiber leases if you can then connect them to local businesses on your route and enable them to cut out the expense of going through the local carrier (usually Bell).
Checking at least your unused fibers periodically for attenuation changes can identify signs of future trouble before it gets out of hand. Having said that, those sorts of "creeping" problems are unusual in well-built systems. Much more importantly, periodic OTDR checks keep your crews familiar with their OTDR, test access locations, as-built network records and any details of particular routes. The next question: Is after-installation fiber damage acceptable?
If so, have you ever spotted a defective fiber? Why do you test incoming cable? Do you keep all the results? As mentioned, cable quality is very, very high among our approved vendors. They ship tens of thousands of good ADSS reels without shipping a defective reel. All of the cable is 100% tested with OTDRs and documented at the factory before shipping. Incoming acceptance testing protects the cable purchaser from damage by the shipping company. Some users don't test fiber ca