Of course it's the last resort; if the enemy has been destroyed, why keep firing?

The point is of course that it isn't the first resort. It's always saved for last, after everything else has been used. In reality, that would be because the consequences of such weapons are usually such that we prefer to find alternative solutions. In poor-quality drama, it's because we need stuff to take up time.

MIT analysis of neural processing: LOL. They said they'd get to the hard stuff after tackling vision - I believe this has been the longest summer on record.