I try to avoid at looking at other men’s genitals.
A. Because I'm not gay, and I wouldn't want anyone (except unattractive to me women) to think otherwise
and perhaps more importantly
B: So I don't feel inadequate
On a slightly different note I was in the gym steam room once, and was pretty much ready to leave, but as opening the door to leave ruins the atmosphere for a short while, and someone had only left a few minutes ago, I thought I'd wait a while longer in consideration to the other guys in the room.
Eventually one of the other guys in the room got up to leave and I thought it'd be sensible to follow him.
He opens the door, walks out, I follow, and without tuning round the guy makes a grab behind him for the door handle to close it.
Eeeek, he momentarily grabbed my tackle!
OK, (thinking quickly) I'll completely ignore it and pretend it didn't happen (happy place, happy place).
He doesn't react either.
A few steps more and he says "That wasn't the door knob was it?"
I confirm it wasn't, he apologises profusely, I tell my side of the story, and we both had a good laugh at our misfortune.
Moral of story: when naked, don't follow people through doors!