Originally Posted by
exilencfc
As Wallybird says delays aren't normally a problem, trains do sometimes gain/lose a couple of minutes here and there but very few get seriously delayed (Great Western, like most UK Train operators, achieves high 90%s of trains running within 10 minutes of their scheduled time)
There is some fudging of the figures, though. A train is considered 'on time' based on its arrival at its final destination, even if it's delayed quite a bit en route then makes up time later on. Train companies are wise to this, so pad out their schedules by adding extra minutes between the last and final stop.
Still though, it does mean you're likely to arrive when by when they say you will!