Wireframes for Chatbot project (Uniplaces)
It seems the physicality of paper, post its and whatnot can reduce the fear of failing because they are low cost, easy and quick to redo and the expectations towards "visual quality" are reduced when compared with something digital.
I think they tend to be more fun as well, of course. And when you are having fun the fear of other people's opinion dissipates a bit more thus making way to a more creative environment.
Something that I believe should be mentioned though is that usually one has to prove this approach (it is not a methodology, there are no rules) over and over, and so it can take a psychological toll on the side of those who kick-start it and have to take the roles of facilitators.
Because sometimes all that it is needed (and quite easy to do so) is someone in a bad mood to ruin an entire morning's session and even make the all company going back to believe that working in silos and jumping straight into assumptions based on the "everyone already know all those things and this is just making us waste time" is the best way.
As such using this approach may require being quite tenacious, but also keeping in mind that a clear agenda and objectives that are understood and created by everyone involved can really go a long way to avoid much work and collaboration getting dismantled.