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Have you ever used terms like "likely" or "a serious possibility" to indicate the likelyhood or probably of some future event? If so, you may be unintentionally miscommunicating.
"Superforecasting: The Art and Science of Prediction" has an interesting anecdote on how even the very best fall prey to this:
A 1951 National Intelligence Estimate report concluded "an attack on Yugoslavia in 1951 should be considered a serious possibility". A few days later, after a confusing discussion with a senior official, Sherman Kent went back to his team asked each person what they thought "a serious possibility" meant. Alarmingly, answers ranged from odds of 80:20 to 20:80! The phrase was so vague that it could create dangerous misunderstandings. It was worse than useless!
Sherman Kent suggested a solution — the terms used by analysis should have standardized numerical meanings. So e.g. something is termed "probable" if there is a 63% to 87% chance it would happen.
Kent's scheme was simple and greatly reduced the room for confusion. But unfortunately it was never adopted.