In uk.railway Steve Firth wrote:
A cross London trip from Waterloo to St Pancras results in a recommendation
to change trains four times.

Waterloo(trains)-Waterloo(LU)-Euston(LU)-Kings Cross(LU)-St Pancras
(trains)

That's not four changes. It's saying:
Walk from Waterloo concourse to Waterloo tube
Catch a train to Euston (tube)
Change to a train to King's Cross (tube)
Walk to St Pancras concourse

It's only flagged as one change: but it explicitly tells you of sections
where you'd need to walk, such as where the tube station is distinct from
the concourse. These are generally obvious and humans would do it without
thinking. But it's useful to have it outlined how long the walk is if you
don't have local knowledge - is it 5 mins or half an hour?

Theo
(who has been using www.9292ov.nl recently and find it quite a good planner
if you've never even set foot in the country concerned so have no local
knowledge whatever. Once you've figured out what the Dutch words mean