Because it satisfies environmental impacts. It will overnight reduce the number of cars on the roads and reduce carbon emissions. It will also reduce the numbers of cars that are bought (a number that has been steadily increasing for years). Less than 5% of our workforce use public transport. Fewer cars will mean vastly reduced traffic and that means the buses will become faster and more reliable and it will reduce wear and tear on the roads for those road users who will still have to maintain a car for practicality reasons. Fewer cars may also encourage more people to use cycling as a means of travel.
Because it satisfies economic impacts. People will spend their money on goods and services. Individuals who are currently economically active because they consider that a bus journey will wipe out nearly £2000 of their minimum wage salary will reconsider working if they can get to and from the workplace for free. We already subsidise our transport heavily (to around 50%) so why not go the rest of the way.
Because it satisfies social impacts. Not only will it empower the economically inactive to incentivise employment but it will increase the social and leisure mobility of low income members of society allowing them to experience more of Northern Ireland and spend their money on goods and services they can enjoy rather than on a bus or train.
Because it satisfies tourism potential. Visitors will be able to leave Belfast much easier and visit more of the province and take longer journeys. We can build our transport network on quality and not solely on cost.
There’s more in the link and tag FreePublicTransport.