The basic concept of a draft is to create a balance of talent throughout a league, and in turn create parity so every team can be competitive over time. The teams that performed the worst the previous season are awarded the first picks and therefore should be able to obtain the most talented players entering the league. This system worked great for the NFL for many years, but after more than a decade since the league implemented a salary cap, the system is in disarray because rising rookie contracts have caused a distortion of value. We've reached the point where having a top-5 pick is not necessarily a good thing, and when a team is happier about picking 15th overall than first overall because they may be able to get an equally talented player for half as much money, clearly something needs to change.
Before 1994 when the salary cap was introduced, if a team drafted a player, gave him a big contract, and he turned out to be a bust, it was still a big pill to swallow. But nowadays if a high draft pick falters it's downright catastrophic because of the player's impact on the field (or lack thereof) compared to his impact against the team salary cap. With a hard cap that requires teams to have total player salaries under a fixed amount each and every season, combined with ridiculous rookie contracts for unproven players, the league has essentially forced it's worse teams each year to play a high-stakes game of craps. If a struggling team drafts a player, signs him to a monster contract, and he becomes a success, chances are they'll sniff the playoffs again before long. But if a team does the same and the player struggles, they no longer have enough money to fix their mistake and may struggle for years as a result of one poor draft pick. And with enormous signing bonuses up front, teams can't afford to just cut the cord after one or two seasons. Think of Atlanta drafting Matt Ryan compared to San Francisco drafting Alex Smith.
There's only one way to fix this problem and I'm not going to suggest the removal of the hard salary cap. If the NFL wants a high draft pick to have actual value and not be a burden, they must do what the NBA does and implement rookie contract and signing bonus caps that are adjusted based on the position of the player. So while it's fair that a quarterback drafted first overall will still make more than a linebacker, regardless of the position teams that are already struggling won't be forced to gamble their future success so hastily.