Think Ill replace my photo with my football. It is very dear to me, so it must represent me.
Will you first try to work out if you recognise the ball? Would you even care who the ball is, or just skip the post as you don't know who it is at a glance.
What about a photo of me and the ball? Do you first try and work out whether I am the ball or me? Why is the ball relevant to tell you who I am, have you met my ball?
What about a zoomed our photo of my whole football team, they are my "family". Would anyone recognise who I am? Without zooming fullscreen?
Off course I know Ill change my profile photo to my eventual offsprings as well.