What freaks me out is that sometimes getting the error message more than once can reset parts of the programmer's brain enough to be able to see the error that "wasn't there" before. And what's equally freaky is how often the programmer then forgets what the error even was once it's fixed.

This is personal experience of course. For me, being introspective about this is kind of like remembering Dr Who's The Silence exist when they're not right there, but somehow it can be done.