Commentators reach for the phrase whenever the team on the back foot scores. It usually describes a structural outcome rather than a fluke, and the structure is worth naming.
Sustained pressure creates the space it exploits
A team camped in the opposition half has its full-backs high and its defensive line pushed toward the halfway line. That is the price of pinning an opponent in.
The space behind that line is enormous and largely unguarded. It exists for the entire period of dominance, not just for the moment the goal happens.
So the counter-attack is not a surprise, it is the standing condition of the match. The only variable is whether the defending team can execute the release pass.
The defending team is set up to score exactly this way
Coaches who expect to be dominated pick a fast forward and instruct him not to track back. His job is to be available the instant the ball is won.
Midfielders in that setup are told to clear forward rather than to build, which looks crude and is a deliberate way of reaching the runner quickly.
When the goal comes it matches the plan precisely, which is the opposite of an accident even though the possession numbers make it look like one.
Shot counts hide who had the better chances
Territorial dominance generates volume from poor positions. Twenty attempts from outside the box and blocked crosses can add up to very little real threat.
One breakaway produces a single shot from close range with a goalkeeper to beat and nobody covering, which is a far better chance than any of the twenty.
Counting attempts therefore tells the wrong story, while weighting them by position tells a story that matches the scoreline more often than people expect.
The psychological effect is real and short
Conceding while dominating breaks the rhythm of the team in control, and the next ten minutes are usually their worst passage of the match.
Players start forcing passes that were not on, and the team that scored gets a second spell of relief it did not earn through play.
That window closes quickly. Most sides re-establish their pattern before the twenty-minute mark, which is why a second counter-attacking goal is far rarer than the first.
The phrase describes the viewer, not the match
What feels against the run of play is a mismatch between the story the eye was building and the result the structure produced.
Anyone tracking where chances came from rather than who had the ball tends not to be surprised by these goals at all.
Which makes the phrase a useful signal about how a match is being watched, and a poor description of how it is actually being played.