I dunno if I'd have said spite but the S&C was built by the Midland Railway due to a dispute between it and the London & North Western Railway over access to Carlisle for Scotland and then some rather good lobbying by other Railway companies.
To start with the LNWR were doing their best to be obstructive with unreasonable demands for compensation to take MR traffic or by making things operationally difficult (attaching MR through coaches to slow trains rather than expresses). The LNWR held the upper hand as they main link between the MR and the LNWR to Carlisle via a branch line that linked from Skipton to Tebay (on the WCML) via Clapham (Yorkshire not London

).
Eventually the MR decided to build it's own route to Carlisle Citadel from Skipton via Settle which bypassed the LNWR and got them straight into Carlisle from where they could work with various Scottish railway companies for onward transport to Scotland proper (the North British Railway to Edinburgh via the Waverley Line and the Caledonian Railway via the WCML to Glasgow).
Before construction began the LNWR gave into the MR and offered them reasonable terms over the existing route but the Caledonian and North British didn't want to be reliant on the LNWR for services south from Carlisle so lobbied for the MR route to be built anyway. And, as history shows, they were successful in that endeavour and the MR had to build it anyway.
So from the MR's perspective it ended up having to build a railway which it no longer needed or wanted solely because some other railways demanded that fullfil the obligations of an Act of Parliament, the original intention of which, had been rendered moot due to subsequent events.
At least that's what I picked up the last time I looked into this in any detail!