> where as the remaining 10% is far more difficult to track and often has no clear stopping point. The problem isn't that it's difficult to track. It's not eve

> where as the remaining 10% is far more difficult to track and often has no clear stopping point. The problem isn't that it's difficult to track. It's not even clear what the remaining 10% is, or if it's 10% to begin with. If you asked 10 people what the rest 10% is about, you'll get 10 different answers.