Eh, as the sibling comment says, it's about the ROI of the new word. If you're defining something with it that would otherwise take many words to explain, or if you want to introduce a new idea, or otherwise use it as shorthand, great. If you're using a new word only once, then why even use it?
Is ROI in this case a measure of comprehension? What about the enjoyment and playfulness of metaphor and expressive language - do these have a negative ROI if they aren't sufficiently terse?
How far do you take efficiency as a measure of communication quality?
Did Kevin have it right when he asks "why waste time say lot word when few word do trick?"[0]
