He did what he was appointed to do - and universally pilloried for it afterwards.
The government had already decided what it wanted to do, the Stedford Comittee, with Dr Beeching of ICI as a member, was set up to investigate "how the Government's intentions for the railway could be put into effect". When they realised what that would mean, half the members refused to support the commitee's recommendations, and its report was never published. Mrs Thatcher even denied the existence of the commitee! Dr Beeching was then appointed by the government to the BRB to produce his infamous report, the govt knowing full well which side of the Stedford Committee he was on!
The implementation of the Reshaping report was then moved down the management structure and left to senior regional managers, who were (in the 1960s) former middle managers of the pre-nationalisation companies. They then gleefully set about doing what they'd failed to do before the war, and that was eliminate the competition. Thus the former Great Central route from Sheffield to London, formerly the LNER, was swiftly run down and closed by the London Midland Region, and in the West Country the Western Region rapidly removed most of the former Southern Railway in its territory.
The proceedure for deciding which lines to close was based on
receipts at stations, measured over one week in November. Whilst not the quietest, it was no where near the busiest either, and produced a lower figure than could have been expected over a whole year. The real fault with this was that it totally ignored traffic generated elsewhere. Many heavily used lines to busy holiday resorts, where most traffic originated in the major cities, showed a fairly low usage on this sort of measurement, and led to many seaside branches, such as Mablethorpe, Skegness, Hunstanton and similar places, as well as the West Contry, being PFC'd - Skegness was only reprieved after a vigourous local campaign.
Receipts at stations also meant that multiple routes were closed. For example between Nottingham and Mansfield there were 3 routes, formerly the Midland, Great Central and Great Northern Rlys. In BR days, it seems obvious that only one route was needed. But because the receipts were split between them, all 3 were closed, leaving Mansfield with the dubious distinction of being the largest town in England without a railway station. This situation was so plainly wrong that BR started the Robin Hood Line (Central Trains - the privatised company in the area took the credit for finishing the project).
British Railways was loosing a lot of money. This was inevitable, given the financial basis which the nationalised railway was set up with. Beeching's plans were to have changed this, but as a lot of the routes remained for freight traffic (until that sooner or later withered away under a subsidised road transport industry - but thats another story!) and the union's support for the plan was bought by the very minimum staff losses, the savings were never realised.
Beeching is universally pilloried now, but he did what he was appointed to do. He could not have forseen the huge growth in demand for transport that has happened since the 1960s, and he did actually have some good ideas. The creation of Inter-City as a brand was his idea, also the concept of high-efficiency, non-stop coal traffic between colliery and power station - the MGR train - was another. Where would international trade be today without the container? Beeching's idea for replacing the pick-up goods trains has grown into the ISO shipping container.
If you can find a copy of a book, "The Great Railway Conspiracy" by David Henshaw, (pub. Leading Edge, ISBN 0-948135-28-X(HB); 0-948135-30-1(PB)) this tells the story of how the government of the day (in my mind the real villains) stitched up the railway. It makes for interesting reading, and alternated beween making me angry that they'd done what they did, and sad that so much that was a way of life for so many, as well as a means of getting around, was simply abandoned for short-term political gain.
Perhaps the real surprise is that after 1) Nationalisation, 2) Beeching's Re-shaping 3) Thatcher/Major/MacGregor's privatisation we still have a vibrant, healthy and growing rail industry in Britain.
(Just my opinion

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