These things are relative, of course, but I smile when I see people talking in shock about trains 7, 10, 15 and even, shock horror, 24 hours late. Such delays in the UK and western Europe are inevitably rare and the result of extreme weather or some sort of fairly catastrophic failure.
Going off topic and international, for anyone familiar with Turkish trains in the early 70s, such delays, certainly 18 - 24 hours, were normal, everyday events at the Istanbul end of the routes from the far east of the country, so much so that my travellin' pal and I actually relied on such late trains to get back into Istanbul after our first trip out east - and this was from Hereke, a station a mere (guess) 40km or so from the Haydapashar terminus. What it got like in winter, with bad weather in the mountains out east, I do not know, but I can well imagine trains could be anything from 2-3 whole days late into Istanbul.
I presume the line to Ankara is, by now, fully electrified and hopefully better managed, but if the lines out to the east have not been modernised and resignalled, I wonder if such wayward running is still the norm?