Teams aren't usually expected to find rookie starters on Day 3 of the draft. That projection is reserved for the first three rounds, where the talent is greater and NFL-readiness generally more likely. Picks 100 and beyond aren't meant to be spots where NFL-ready prospects or top-tier talents are supposed to slip to.
But it's the inefficiency of the draft process and the inability for teams to perfectly project talent that make the NFL draft so much fun each year.
It's difficult to adequately project which Day 3 picks will end up as starters, but it's proven each year that double-digit picks in that area get a chance to play early as rookies.