Deploying fiber in the field is often a dirty job. Installing in new buildings means working on a construction site, with all the mud, dust, and rainwater that this entails. Digging trenches for fiber ducts adds to the mess, and a sudden storm can turn the whole site into a quagmire.
It isn’t necessarily much cleaner indoors, with deployments in existing buildings subject to dust and debris from the installation methods needed to create space for fiber, such as drilling into ceilings and walls.
There are three key reasons that all this dirt and contamination is an issue during fiber installations: