The local loop, also called the "last mile", is the connection from a telephone exchange to a subscriber's premises.
The local loop is enormously expensive for new entrants to replicate and gives incumbent operators a huge advantage. The incumbent operators had lines already laid to every fixed line subscriber before the competition started building their infrastructure.
The problem has also been significantly reduced by new technology. Cable TV companies have an alternative network that is capable of carrying both voice and data. In some countries fixed radio links are used to reduce the cost of installing local loops. Mobile phones also now cost little enough to provide alternative networks.