In SciFi great ship tech, what is the general lore behind why shields start at 100% and lower when confronted with any type of weapon or physical blow? Most shields deflect objects (not electrify/torch them) in SciFi. This infers more of a mag field or gravity. If that were so, a mag field wouldn't weaken when a non-mag force is applied.
It's fiction...I know...but so many ships have been needlessly blown up.
@steaphan "Shields" are usually portrayed as you describe -- an energy field of some sort, which I'd think would either be enough to deflect a projectile, or not. Wouldn't seem to be something that should degrade when confronted.
There's at least one Star Trek reference, though, that explains shields as a replicated super-alloy projected into the space surrounding the vehicle. It might make sense for this to weaken or dissipate under impact and require time and energy to re-fortify.