Another factor is that it cost Verizon around $750 per house just to install fiber to the neighborhood.
And then _another_ $600 or so to actually connect each home that signs up, for a total of $1350 per connected home.
Some analysts say it's more like a total of $1800 per connected home, but in either case it's a lot of money to invest. It also explains the high ETF, which wouldn't even come close to paying off the investment.
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The final factor is LTE, which will be far cheaper to deploy. Look Ma, no cable! Although that means (as usual) that Verizon Wireless is stealing business from Verizon's landline division.