Not necessarily. I'm not being contrarian for the sake of it. This approach that takes the first third of the time presenting the problem to an audience that

Not necessarily. I'm not being contrarian for the sake of it. This approach that takes the first third of the time presenting the problem to an audience that arrived to hear the solution to a known problem can sometimes be annoying. It could just as well be done this way: 1. State the problem in a short less than 1 minute summary. 2. Present the solution and sustainability etc (bulk of the presentation) 3. Then, lastly, present the problem that most already know - only this time in detail.