There is a lot of value of making decisions based on the factual objectivity of data. It feels good because we believe that we are making an accurate decision. For example, we might judge our personal success on how much money we have in the bank account. After a year of hard work, I can look at the balance in my accounts, sum them up and decide if I am more or less successful than last year. This is a convenient metric, but is it the truth?
You can quickly shoot holes in this use of a single data point. For example, what if I spent a bunch of money this year on a large investment, some rental property, or perhaps a business, or other investment. My bank account can be lower, but does that mean that I am less successful? What if invested in education for a member of my family? Would you call that less success then if I had a larger reserve of cash in the bank? So in this case, the single bank account metric does not work very well.
Lets say that I decided that I would judge my health by what the scale says every morning. Would this data speak the truth? Well, no it would not. I can be pretty unhealthy and weigh less or more. I can have very little muscle tone at all and weigh less than if I did. So we have learned, when it comes to health, that a single metric never speaks truth.
As I look at my personal life and my business life, we oftentimes fall for the trap of judging our success, or efficacy by the use of single metric. It is awfully convenient to use a single metric, easy to collect, easier to monitor. However, it rarely speaks the full truth. In almost every realistic scenario, it would take multiple metrics to decide what the health of a particular situation was. For example, I might want to look at cash on hand, but also network, and income from passive sources as the three metrics to determine financial health. Those three combined together would certainly tell a more accurate story then just bank account balance. In terms of health, I could look at weight, but also body fat percentage, and waist circumference. Those three together would provide a good picture, although certainly not complete.
We often judge ourselves, and others by the use of a single metric, the problem is that in almost every scenario that is an error. You cannot possibly get the correct frame of reference on anything looking at it from only one viewpoint. So before you judge yourself, or another harshly, consider adding a couple of other data points.