Upside is the football term for "speculative".
The NFL basement is littered with guys with "upside". Upside means they haven't done anything yet. It means that they have all the physical attributes but have never played anywhere near that high ceiling. Lance has proved near to nothing. He's just big, fast, and has a strong arm. That does NOT make an NFL QB.

Lance simply has not played enough, nor against good enough competition, to have any reasonable idea how he could do in a Pro style offense against Pro D's. I wouldn't be shocked to see if he drop into the last third of the 1st round. As for me: he's a 2nd round pick at best. Why anyone would take Lance over Jones or even Trask makes no sense to me.

He needs so much development and even then who knows if he'll be able to deal with the faster processing needed.