A printed newspaper is not a single fixed object. Copies produced through the night differ from each other, and the reason is the time it takes to move paper across a country.
Distance sets the deadline
Copies travelling furthest must leave the plant first, because they need the most hours on the road to reach shops before opening.
Those distant copies therefore close earliest, and anything happening after that point cannot appear in them.
Copies for the city around the plant can be printed hours later and still arrive on time, which creates a natural sequence of deadlines rather than one.
Each edition replaces what it can
Between editions, the pages that can still change are updated while the rest of the paper stays as it was.
Features, listings and long-planned pieces are printed once and left alone, since nothing about them will improve overnight.
News pages, sport and the front are held open as long as possible, because those are where late information changes the value of the copy.
Sport is the classic driver
Evening fixtures finish long after the first edition has left, so the earliest copies carry previews or partial reports.
Later editions replace those pages with full reports written against a deadline measured in minutes after the final whistle.
This is why readers in different regions could see genuinely different coverage of the same match on the same morning.
Late news forces a remake
A major event breaking after the first edition triggers a remake, in which the front and several inside pages are rebuilt and the presses restarted.
Doing so costs press time and delays the remaining run, so the decision weighs the significance of the story against the risk of copies arriving late.
Editions that carry an early front and a late story inside are the visible compromise between those pressures.
What changed as print volumes fell
Fewer plants and smaller runs have reduced the number of editions many titles produce, since consolidation lengthened the distances involved.
Continuous online publication also removed much of the purpose, because a reader wanting the latest development no longer waits for a later edition.
Edition marks still appear on printed copies, and they remain the simplest way to tell which version of a day's paper a reader is holding.