The overlap is usually on when your movement creates a new passing option without leaving the team completely exposed.
Look at the winger first. If they have received inside and drawn the opposition full-back with them, the outside lane may be available. Then check the ball carrier: are they secure enough to find you, or are they under pressure and likely to lose it? Finally, check what protection exists behind you.
You do not have to receive the ball for the run to be useful. An overlap can drag a defender away and give the winger more space inside.
The mistake is making the run automatically every time the winger comes inside. Sometimes holding underneath gives the team better balance.
Think of the overlap as a response to the picture, not a responsibility you must complete on every attack.
