There’s probably some sociology at play here. If you ask a guy and a girl to look at their own finger nails, they usually do it differently.

Guys tend to bend their fingers with their palm facing towards them - since their main concern is checking if there’s any dirt under their nails.

Girls tend to straighten their fingers and point their palm away from them - since their main concern is how their nails looks to others.

So yeah… when guys are taking dick pics, they need to override that tendency and be more mindful of other people’s perspectives.