The starting contact changes the stroke’s context
When the cue ball is declared touching a ball on, WPBSA’s rules require playing away without moving that object ball. In the specified situation, a fresh visible collision with that same ball is not required to explain the legal stroke.
The cue ball rests against a red. After the referee’s declaration, the player sends it towards a cushion while the red stays still. Watching only the outgoing path can make it seem the player failed to contact any required ball. The starting contact supplies the missing context.
Listen before the shot
The referee’s identification is more useful than assuming that two balls appearing close on television are touching. A small gap can be invisible from the main camera. Conversely, a declared touch can disappear from view once the cue ball leaves.
This example concerns a red that is on, not every possible combination of touching colours and nominations. Keep the declared ball’s status in the record. The aim is to explain why playing away can make sense, rather than treating any apparent near-contact as permission to ignore the ball-on requirement.
Questions answered
Does a tiny-looking gap prove the balls were touching?
No. Use the referee’s determination.
What must stay still in the simple example?
The touching red.
Sources & further reading
Official references for the subjects discussed. Service terms and device software can change.