Today we dig further into this “measurements don’t need to be exact to be useful” idea.

Here we go…

At one point I needed a new heater core for my car.

The heater core is the little radiator that sits inside your car, behind the dashboard where you can’t see it. When you turn on your heater, air runs over this thing and it warms your car. It looks and acts exactly like a little version of the radiator in your home.

I figured the heater core is way too specialized, no one’s ever going to make replacements for it, I definitely can’t just go to the auto parts store and buy one. So instead, I went to the hardware store (Home Depot, for those of you who recognize the name) and I bought the supplies I would need to make one myself: Some copper tubing, some copper sponges, a blow torch for the welding, etc.

I went back home and, since I didn’t have a shop, kneeled on the sidewalk outside my apartment in Seattle and assembled my little homemade heater core while passersby looked at me strange, probably wondering, “Why is this guy blow torching copper tubes on the sidewalk?”

Anyway, to install the heater core, you have to remove the dashboard. And in removing the dashboard, I was amazed to see how many wires are back there. For every gauge and every switch and every knob on your dashboard, there are at least two wires running to it.

Which means a lot of wires.

I installed my homemade heater core and bolted the dashboard back into place, careful not to disturb the wires.

Unfortunately, my homemade heater core was completely ineffective. It produced no heat whatsoever. And what’s more, I found out the next week that actually there was an entire stack of real heater cores for sale at the auto parts store, and those heater cores were even cheaper than the money that I had spent on supplies to make a completely ineffective core myself.

So I bought one of those real heater cores, removed my car’s dashboard again, installed the real heater core, and put the dashboard back on again. Everything worked fine.

In other words, twice I got to see just how thick and intimidating that nest of wires behind the dashboard is.

For me, an amateur, if I wanted to describe the number of wires behind a dashboard, I could use the word shtload (“there is a shtload of wires behind a dashboard”).

However, if I were building a dashboard, I would need to use a much more exact number, like “621” (“there are 621 wires behind this particular dashboard”).

And then if I were a professional mechanic talking to a customer, I could probably just use something in between, like “hundreds” (“there are hundreds of wires behind a dashboard, you don’t want to go back there”).

The point of all this is that your measurement doesn’t have to be exact, it just has to be good enough to improve your decision-making process (in this example, “do I want to take the dashboard off again”). In my case, the useful number didn’t even have to be an actual number (“a sh*tload” was good enough).

As long as your measurement is good enough to help you improve your decision, the measurement has done its job.