Take a look at this clip:
Now picture the part of the movie where Marty DiBergi is being shown Nigel Tufnel‘s guitar collection:
NIGEL TUFNEL: When we play, audiences can feel our power, which is colossal, really.
MARTY DIBERGI: You certainly are loud.
NT: Normal instruments can’t handle our massiveness, so I had this made special. It’s a Flying V, built exactly to scale.
MDB: Well, it’s not really to scale, because it’s a lot bigger than you are. Can you even play it?
[Tufnel stares blankly}.
MDB: I mean, maybe if you were a giant.