This is key to understanding bipolar: it has an "upswing" phase in which someone has more energy and less inhibition. Increased self-belief as well. It can, if you're lucky, be just the right thing to catapult someone into incredible creative works.

The risk is that risk-taking may not pay off, and the inhibitions may have been there for good reason. Not to mention that there's also a downswing phase which looks like depression and comes with elevated suicide risk.