About two years ago, when reading the book "Thinking, Fast and Slow" book by Daniel Kahneman, it occurred me the concept of heuristic question. The idea is simple, but powerful:
Whenever you ask a question, the person will answer the heuristic question.
The heuristic question is the simplified version.
If I ask you if you think that candidate A will win the election, it would be fair to make a complete analysis before answering: at least a minimal thinking based on reason. But we reply right away! This is because we are most likely answer the heuristic question:
Do I like this candidate?
See that one is easy to answer, the other is hard!
People do it so daily that it is even hard to not see once you learn this concept: you may have, like myself, why people tend to answer a different question when tough questions are asked. Different from the speed of light, which requires special speeds to be perceived, this concept is easy to see, once you stop to observe. We do it all the time, and people do it with us all the time!
Some interesting examples come from "Asking Questions: The Definitive Guide to Questionnaire Design".
Some questions can have strong differences if we change slightly the question: the question is the same, but we change the wording, even slightly, you are going to get a different answer in a poll. Some cases the different can be strong.
An interesting observation is that general questions tend to be easier to word, with less risk of getting huge differences between different formulations. The more specific the question, the higher the chances of discrepancies between formulations. I would guess:
Heuristic questions may be like associative memory, we build answers faster for general questions, and socially speaking, several heuristic questions individually may converge to the same general questions.
Just some speculations!
The core idea is: whenever you ask, or whenever you are asked.
Remember: what you are answering may not be the properly question. If the question is important, make sure to give proper attention to the correct question; or make sure to guide the person the question is addressed to properly.
Main reference
Asking Questions: The Definitive Guide to Questionnaire Design -- For Market Research, Political Polls, and Social and Health Questionnaires. Book by Brian Wansink, Norman Bradburn, and Seymour Sudman
Thinking, Fast and Slow. Book by Daniel Kahneman