A few months ago I was flying the same R22 every couple of weeks and so got quite familiar... to the extent of cutting my pre filght to a quick walk round, sightglass and con rod check, light up and drive off.
This rapidly changed when an older private driver, watching this young pup asked how confident I was with my checks? To keep this short he pointed out that despite the fuel guage showing about half in both tanks, actually dipping the tanks revealed that I was about to attempt an hours flight with roughly half an hours fuel.
Now, I physically dip the tanks EVERY preflight.