Players do only roll 😊 when they roll a result with Backlash, the GM then decides what that Backlash will be (typically guided by common sense). So the players take action (as long as the GM seems it a reasonable thing to do), the dice decide whether it’s successful, and if they have Backlash the GM decides what it’s going to be.
So when a player decides to engage an opponent (let’s say with Might) and they roll a result with Backlash, the GM might choose to deal them a wound if it makes sense in the combat scenario. I hope that helps 😊