When polyglots answer the question: "How many languages do you speak?" with a number, What are the various criteria for deriving it?

I speak three languages well enough to be employed in positions requiring that language. I speak many more with varying degrees of proficiency.

I would normally say three,. but I might add a few more because I understand many things when I listen to speakers.

I can exchange pleasantries in many more, but I do not think I should count these.