Let's say you want to check whether members of the social club think it would be a good idea to hold a big party next month. You put out a questionnaire (or use Survey Monkey as we do). Most people reply yes, a party sounds great to them.
How many will come?
Who knows? Research over the last 40 years shows almost no connection between attitudes (Wow a party!) and behaviour (showing up).
You'll improve your chances if you focus on the behaviour (Would you come?) and especially if you ask them to put their name on their replies.
You can use the same ideas in conversation or at a meeting.