I find that whenever I get out of my "normal routine" of plane assy at the field / preflight check, there's going to be something go araie. Examples of this would include bs'ing with my club buds, etc.

I had one of my friend's kids come over one time and I ended up focusing on him instead of my plane. In the control surface check, I'd discovered that I didn't hook up my ailerons. BUT - I caught it.

Whenever I get out of the normal routine now, I just put everything down and wait till the "normal routine" presents its self (comes back), and I'm able to focus on the plane / radio.