It takes hearing new information seven times in order to retain it. For you to really hear something and internalize it, you have to be exposed to it seven times.
So everyone is at a different stage of hearing a message. For some, it's the first time. For others, it's the third time. Some people may be on the verge of hearing something for that magical seventh time. That's what I call the Magic of 7.
These seven impressions have to come from somewhere. People are exposed to messages in many different places. You may be the first to share an idea with someone or you may be the fifth. If so, the idea isn't going to sink in when you deliver it. You're just planting the seed.
But here's where it gets interesting: it doesn't matter if you were the one to make the first six impressions, you just have the be the person that delivers it the seventh time.