Nationalising the railways prevents the consumer being exploited by profit-hungry companies

• The UK is seeking to nationalise the railways under one organisation called [Great British Railways] which will provide contracts to train companies to run trains on the track.
• This system will provide a more accountable way to hold train operators to account. The government can be held to account, and as a result, a nationalised railway will be able to do the same. This can lead to increased customer satisfaction. as well as increased transparency.
• The railway industry in the UK depends largely on government investment anyway- nationalising it will help identify where further investment is required on a national level.

Some believe having privatized railways in the UK is best for efficiency, morale, and safety in running the lines.

• "The issue is not profit but structure. Individual lines of route must be separately managed and in complete control of their fixed and running assets. That is the key to efficiency and corporate morale," writes Simon Jenkins for The Guardian.

• British journalist Christian Wolmar said he thinks that the break-up is worse than the privatization: "Every railway man I've ever talked to will privately admit that it's no way to run a railway." Part of the reason is that government involvement can be a slippery slope to government ownership.

• Overall, some believe that the privatization of railways in the UK has functioned quite well: passenger numbers, fares, public subsidy, and overall safety of the railways have been considered some of the greatest benefits of maintaining the privatization.

Not privatised enough
Nationalisation is a popular opinion and it is controversial to go against the grain.
The reason trains suck (they are better than they were under the government) is because they are not privatised enough:

• Around 40% of rail fares including season tickets, anytime and off-peak tickets are regulated and so the government is in control of how much they cost.
• The only privatised part of the railways is the day-to-day operation of the trains and even this is on a short-term franchise agreement with the government.
• The government is also responsible for all capital spending on the railway, as well as the maintenance of the track, as well as all signaling related to the day-to-day operation of trains is operated by Network Rail.
  Lack of competition leads to high prices and lack of innovation,.
• The infrastructure hasn't been updated in over 160 years massive investment is required to bring this up to scratch.
• Train operator's profit is in the region of 3% on average and is reinvested in training, facilities, and railway infrastructure, with only part of the 3% going to shareholders in dividends.
• If you ignore the state’s contribution to infrastructure costs, a number are profitable and some considerably so – these include South West Trains, Greater Anglia, and Thameslink. Operators have benefited from both the passenger increases and reduced charges for track access.

At the end of the day if we look to America you can see examples of both privately built railroad infrastructure and government building. The union pacific had 10s of millions of dollars and it failed they were extremely inefficient due to lack of a profit motive. You also had the great northern which was completely private, extremely efficient, and cost-effective. It went down in history as one of the best railways in the world at the time.