Many people have attempted to build the perfect home. One home builder told me that it is the 7th house that is just right. I am confident he wanted to sell me another house.
My wife and I custom built our 5th home. It was not perfect. Immediately we realized how quickly hardwood floors deteriorate with four kids. The 20 foot ceilings became a problem when it came time to change light bulbs. The basketball court in the back yard was perfect for me, but not for the family that bought the house when we sold. Pretty confident that another build or two, we would get it just right.
Thinking through what other areas in life that the 7th time's a charm rule can apply.
Posting a blog.
Preaching a sermon.
Giving a presentation.
Writing an essay.
Composing a song.
Maybe 7 isn't the perfect number, but doing an activity over and over must have some value. Anything worth doing 7 times is worth doing well. If a project was done well the first time, it might be close to perfect by the 7th time.