It was Dave Elbourne who put me on to connecting leads back in the very late 1980s with his layout "Scotland Street Yard".
At the time, model railways layouts tended to be adorned with dangling leads to transfer power from one board to another. While these worked, they were prone to getting caught on things as the model was transported around. Snagging one during set-up could result in a few broken connections and some swift soldering iron work before operation could commence.
Dave worked for BT back in the days when quality and reliability mattered more than all-out profit. Taking his cue from this, and I suspect the easy availability of leftover free connectors, he made up all the layout connections as lead - bundles of wire with a plug on each end.
Sockets were fitted to both layout and control panel and dangling wires were no more.
OK, you could forget the leads and there were twice as many connections to be made but to my mind, the results were an awful lot tidier.
On most of our layouts, I've gone for leads. Only Flockburgh has dangling cables and that's because I used obsolete chunky plugs and sockets and couldn't get enough to make them self-contained. The result is a panel with long bundles of wire floating around that I am always terrified will snag on something.
So far we have been lucky, it can't last, so Edgeworth has leads.