It depends on situation. I'll use penis enlargement and sex .
I'd say for penis enlargement going for a maximum growth phase
Length is most important since I've gained 0.25-0.5 inches at most since I've measured twenty two years ago. I ve put in over three years of hanging every day four twenty min sets so since seems difficult for me. I know if I'm doing many sets throughout the day at least a few hours afterwards my EQ probably will be down .
Hardness- simply put having full EQ feels amazing
Desire, how turned on I am. This can be from using my imagination, to type of porn, to how attractive I find female I'm having sex with. Of course looks matter, youth, and personality.
Girth would be last since I started at six inches and now 6.25. being that it seems to come easy for me, I'm still extremely thankful that I have it.
Now it is for sex
I'd say deep down desire matters most how much I like her, of course looks matter , we are human and any youthful cute attractive woman can cause more desire
Stamina would come next I like to rock her world for long time. If I cum too early I can cuddle, touch caress her body then eat some pussy before I can get a quality erection again.
Hardness of course.
What about you Big Al, what is important to you?