Service Strategy: Risks vs Challenges

Have you ever differentiated between RISKs & CHALLENGEs?
I came across these two terms again in trying to understand ITIL-Service Strategy.

Kevin Archbold explains it well below:

A risk is something that could happen, that you'll look to prevent if possible, or have contingencies in place. 

A challenge is something that is already the case that you'll have to deal with.

Article:
http://sebastianmarshall.com/risks-vs-challenges

Enjoy your day!