Simplicity
We’ll keep this simple.
This research has been around for a few years, but it made the rounds on Marketing Twitter again this week and is always worth keeping in mind. In short, the more messages an ad tries to communicate, the less likely any of those messages actually gets through.
The best executions send one simple, clear message.
(You can go here for a slightly longer discourse on the topic, and an amusing example of a radio station that violated this rule.)