A goal scored from a rebound is usually described as scrappy or fortunate. Teams that score them repeatedly are not luckier than everyone else; they are shooting in a way that produces reachable rebounds.
Saves travel in predictable directions
A goalkeeper diving to his right pushes the ball out to his right, because the hand meets the ball on that side and cannot redirect it back across the body.
Low shots produce rebounds along the ground into the six-yard area. High shots produce parries out towards the edge of the box.
None of this is random, which means a runner can be sent to the likely area before the shot has even been struck.
Hard and low is a rebound-generating shot
Goalkeepers hold shots they can get their body behind. Anything that forces them to extend at pace is likely to be pushed rather than caught.
Low shots to the corners are the hardest to hold because the keeper is falling as he handles the ball and has no ground to brace against.
A striker choosing power and placement low is therefore choosing between scoring outright and creating a second chance, which is not a bad pair of outcomes.
The second runner decides whether it counts
Rebound goals require somebody arriving late into the area rather than standing in it. A stationary attacker is marked; an arriving one is not.
This is why the far-post runner and the arriving midfielder feature so heavily in these goals while the centre-forward who shot is on the floor.
Teams that coach this treat the shot as the start of a phase instead of the end of one.
Why defences struggle with the moment
At the instant of a save, every defender's eyes are on the ball and their body shape is turned towards their own goal.
Turning to find a runner behind you takes longer than running onto a loose ball in front of you, so the attacker has the advantage.
Defensive coaching addresses this by demanding that one player never watches the shot, which is difficult to enforce.
What it means for judging strikers
Rebound finishes are counted in totals but rarely in reputations, because they look easy on the highlight.
The skill is in the arrival, the timing of the run and the willingness to keep running when a teammate is shooting.
Strikers who score a steady stream of them are demonstrating a repeatable habit rather than benefiting from an unusual run of fortune.