Sometimes it may be useful to prevent voting results from showing while a poll is in progress. For instance, when you run a contest and you want to avoid any influence on judgement.
So here is how it works:
The new feature is available when you create a new thread with a poll, or (you may have to ask a team member to do that for you) when you modify an existing poll. At the bottom of the poll setup page, there is an option to "Hide results", which can be switched on/off. When it's switched on, the results will be available for public viewing only after the poll has been closed or has expired. Note that the poll starter as well as team member can always access the voting results.
See screenshots for a visual guide.