Raw skill is not the only factor to determine the difficulty of a shot. Many battlefield conditions can alter the accuracy of missile fire, and we represent these with a series of shooting modifiers. Shooting modifiers are applied to the dice rolls before they are compared to the score needed to hit, making the shot more difficult, and therefore less likely to succeed.
Continuing the earlier example, if the five Empire archers had a -1 modifier applied to their shooting attack, all of the dice would count as rolling one point lower than they actually did. As a result, those dice would need to score a point higher, and instead of needing 4s to hit, they would now need 5s. Accordingly, only one archer would have hit.
The shooting modifiers are cumulative (except when noted otherwise), and are as follows:
Moving and Shooting
Firing at Long Range
Standing and Shooting
Target Behind Soft Cover
Target Behind Hard Cover