Gonna be honest.
This is what I think is happening.
(forgive me if this theory was always discussed, I skim through most of the posts on here)
I think Mark was thinking it would take a week or two for the community to reach the first goal, which would have given him enough time to book a photo shoot, sort through and ok a few photos. Have them touched up. Set up the account, (cause it takes like 24 hours for them to approve your account/tax info).
And when he saw that the community completed the first requirements within 3 days. He may have been a little surprised, but him being a business person, decided to use this momentum to push another requirement to help give him more time to set it all up.
But that is what I think.