No question about that, but the large majority of very good QB prospects are selected very early in the draft. If a QB prospect lasts beyond the first few picks in an NFL draft, it is because that prospect has either some less than ideal traits or has unanswered questions such as inexperience, coming from a non-pro style systems, injury history, size, arm strength, etc - For sure, it doesn't mean that prospects like that can't succeed, but the very best prospects go very early.