I’m not sure people in general understand the difference between risk and uncertainty so here is an update on an article dated 2012.

Barry Ritholtz does a good job in the article quoting Michael Mauboussin

http://ritholtz.com/2012/12/defining-risk-versus-uncertainty/

Risk: We don’t know what is going to
happen next, but we do know what the distribution looks like.

Uncertainty: We don’t know what is going to happen next, and we do not know what the possible distribution looks like.

The distinction is important in the area of strategic planning.

ROIs for initiatives should always include a Risk Assessment (worst case, expected, best case).

Approvers of ROIs are well advised not to expect to end up too close to the bottom or too close to the top.

In respect of uncertainty, ROIs should also always include exit strategies.