When a ship starts to take hull damage, you can see the condition of it deteriorate. Generally, if I see it pass through multiple stages of damage in a short amount of time, then I'll charge in after it, because that means we were doing a huge amount of damage. If, though, I see that it may only change once, then I will linger at whatever distance I was at and keep the damage up, because flying in closer can give that enemy team an easier time shooting at us, and give my team a harder time aiming for specific components.