Agaricus bisporus
"Filthy 1234, are you ready?". "No, waiting on the cabin" AAAAARGGGHHHH!!!!! What's wrong with the correct "Negative"? What kind of idiotic gloop-speak is "waiting on the cabin"? Are you serving the cabin tea? Do cabins even drink tea? Just "Waiting for the cabin" would be bad enough, but on it?
Since the expectation is for turbine aircraft is to be ready upon reaching the hold lines, most of the time you hear "cabin not ready" (or some derivative) as an explanation as to why a takeoff clearance or line-up and wait instruction is refused. We do this all the time, and sometimes an explantion is required..."Unable high speed due to turbulence", "Unable FL ..... due to weight", "Negative RVSM due to equipment", "Unable 250 degree heading due to weather" etc. etc. Because of the expectation by ATC that aircraft are ready upon reaching the hold lines, explaining the reason for refusing further clearance is appropriate.
Responding to the much-less-frequently occuring question "Are you ready" with a "Negative due to cabin", instead of "Negative" (with no explanation) is technically extraneous but understandable, because in the pilot's mind he's essentially refusing the clearance he would expect next if he answers in the affirmative.