Do ISPs really need to lay more fibre?

I was talking to the people installing the fibre and they said some interesting stuff.

Apparently only about a fourth of the fibre actually burred ends up getting plugged in or used. Because they always want redundancy they will install cables with more fibres because they allow for some breaking when they are being burred, there will also be redundant lines so if the line they are using stops working they can switch over to another without having to dig holes again. Is his just how the telephone networking companies work in Australia or is this the same every where?

It's a government project, they're just padding the bill :P

But yeah, I imagine that would be a pretty common practice as the cost of laying the cable is orders of magnitude more expensive than the cable itself. So you're much better off putting redundant cable in then having to go back and do it all again later.