...of having to go through the motions even when you already know?
Got called for a floor drain. Was thinking main line befor I even rolled out. Pull in and wtf is that excavator doing parked on the far side of the building? I mean, you just know. But I make sure that, yes, its a main line, and throw the jetter in, and sure enough hit a brick wall about 90' out, which is the right distance. And shove the camera in and locate it, and sure enough it's right on the edge of what's been dug and nicely compacted and backfilled for whatever reason.
And call the excavator, which I'm so happy that I recognize the machine, and tell him I think he needs to get back over here and open this hole again even though it's Saturday and I bet you stayed late last night to get this buttoned up. And spend time on the phone smoothing feathers and being diplomatic and noncommital because I know this guy, and he's all right. And 4 1/2 hours later, because I stick to be a d1 operator and make sure I'm right, it's handled when I could have rolled out after 5 min.