Cardinals coach Bruce Arians (left) and General Manager Steve Keim speak to the media Tuesday during their pre-draft press conference.

Steve Keim has said – often – that it is crucial as both a general manager and a scout to self-evaluate and learn from errors.

As Keim prepares to run his fourth draft as the GM of the Cardinals next week, he understands that he'd like a better percentage with his early picks. In three years, the Cardinals have taken guard Jonathan Cooper, safety Deone Bucannon and tackle D.J. Humphries in the first round, with linebacker Kevin Minter, tight end Troy Niklas and linebacker Markus Golden in the second round.

"Hits and misses, like a lot of teams," Keim said Tuesday, as he and coach Bruce Arians conducted their annual pre-draft press conference. "But I don't like to think about what other people are doing. I try to look at what we've done, and I've said all along, it's a

humbling business. If you are honest with yourself, you see where you made mistakes. To grow and get better, you have to be honest, look in the mirror and say, why did I make a mistake on that player and what did I miss?

"Hopefully with future years and more experience, you can eliminate those problems. Probably a 'C' if would grade myself. There is certainly a lot of room for improvement."

Bucannon has been a solid choice, although he is playing linebacker. Cooper struggled before being traded this offseason to the Patriots, while Humphries is expected to earn the starting right tackle job after the Cards kept him inactive all season last year.

Golden had a promising rookie year, while Minter finally earned regular playing time in his third season. Niklas has yet to impress after two seasons, although he, like Cooper, has battled injuries that set them back.

"Injuries change everything," Arians said. "Some guys, never been hurt in college, and then all of a sudden they get here, they get two or three freaky injuries."

As of now, the Cardinals don't have a second-round pick in 2016. That, with Cooper, went to New England in exchange for linebacker Chandler Jones – and the absence of such a pick doesn't faze Arians.

"Just write Chandler Jones' name on a tag, you'll be happy as hell," Arians said with a grin.

The first round pick could go in multiple directions. Conventional wisdom has the Cardinals taking either a center or a cornerback in the first round, although there are scores of variables that impact that choice. Not surprisingly, Keim said the Cardinals are leaving open the option to trade back but also forward, if necessary.

Two interesting notes about potential positions to draft: Both Arians and Keim noted that plenty of NFL centers played other positions on the offensive line in college, leaving open the possibility of a later non-center pick to become the new starting center. Arians also said this draft, unlike recent ones, offers more intriguing quarterback-of-the-future possibilities, including in the later rounds.

Another twist to this year's top 120 board – which the Cardinals recently completed and will be the list off which the team will make its selections – was the addition of both a "character" and "football character" grades for players. Potential draftees got rated somewhere between "A" and "F" in both categories, helping with choices.

The idea is that some players make mistakes in college (character), and only those with strong "football character" have a chance to earn back an opportunity.

The Cardinals have already tried to figure that in in the past, a reason they took a chance on safety Tyrann Mathieu in 2013 – his football character was strong. Mathieu was also an example of what Keim has done very well in the draft, the "A"-level selections later on, including taking Mathieu, wide receiver John Brown and running back David Johnson in the third round.

All three would be considered potential first-round talents in a re-draft.

"This time of year you can get so caught up in the buzz or the hype," Keim said. "You have to trust in the process.

"As long as you believe in the player, and you believe in your grade and you believe in your eyes, that's all that matters."