What is Revenue Management ?

Revenue Management (aka Yield Management) is usually refered as the art of optimally selling perishable goods.

Then this definition is usually followed by the facts that Revenue Management uses a set of highly complex mathematical technics.

While being true, the practice of Revenue Management is a bit different.
Imagine you have 10 icecubes for sale in a really hot day and no freezer. If somebody offers you 5$ to buy an icecube you can :
    1 - sell it
    2 - bet that someone else will come and offer you more.
 What is at stake is that if you lose, you end up with either less than 5$ or (worse) some valueless water. And this is Revenue Management.