Winston Churchill once sent back a pudding, saying that it had no theme.
The importance of theme should not be dismissed. What is the theme of your presentation? Your report? Your marketing pitch? Your meeting? What central idea do you hope to convey? What goal do you hope to achieve?
Finding a central theme and then attaching the ancillary branches to the trunk forces us to consider what we are truly about. Without a theme, we can appear to be disorganized or opportunistic.
[Old joke: If you ask mathematician "What is 2 + 2?" the response will be 4 whereas an attorney will shut the office door, lower the blinds, turn up the radio, and ask, "What do you want it to be?"]
Sometimes, we are fortunate enough to have a theme to a day, a morning or an afternoon. We are usually restricted to finding themes in a specific project. That can be both tough and fun, but it is crucial if we are to make ourselves clear.