re: Jalen Collins and Vadal Alexander NFL grade

So these guys that are told to stay in school but might still declare for the draft - do you think they disagree and think they will get drafted or are they just okay with any amount of money as long as they make a team? I would assume some guys just want to start collecting any amount of money as soon as possible and hope to earn the big bucks on the second contract. You just give up any guaranteed money on your first contract if you are drafted low or not at all.