What's the saying, "the last 20 percent takes 80 percent of the time"? That's why people don't finish. Once the fun part is over, they lose interest. The habit

What's the saying, "the last 20 percent takes 80 percent of the time"? That's why people don't finish. Once the fun part is over, they lose interest. The habit to develop is seeing things through that last bit of polishing.