After the Seattle Seahawks’ 2015 season ended, head coach Pete Carroll acknowledged that the overall offensive line performance was not good enough.

"I think it’s still a work in progress," Carroll said the day after the playoff loss to the Carolina Panthers. "I don’t think we’ve nailed it yet. I think this needs to be a really competitive spot again, and we’re going to work really hard to build it up. For the course of the season, we weren’t consistent enough. We found a real good rhythm, but we can’t start and go through that again. We don’t want to have to experience that if we don’t have to, if we can avoid it."

To most observers, the meaning of Carroll's words was obvious: Work really hard to build it up. The Seahawks were going to add talent on the offensive line this offseason. It was going to be a priority. And the unit they would put together for 2016 would provide a significant upgrade.

Yet here we are on March 29, and that hasn't come close to happening. The team lost left tackle Russell Okung and right guard J.R. Sweezy in free agency. The Seahawks have added Bradley Sowell and J'Marcus Webb. Sowell hasn't started a game since 2013 and seemed somewhat surprised at how quickly the Seahawks went after him. Webb will be on his fourth team in five seasons. He played right tackle -- the position at which the Seahawks plan on starting him -- for all of three games last season.

The holes that existed at the end of last year still remain. They are actually even more glaring now.

So it's fair to ask the question: What exactly are Carroll and general manager John Schneider thinking?

Below are three factors that likely play into the team's decision-making process on the offensive line.

1. The run game has worked with a rotating cast of linemen.

No one would argue that the Seahawks had a great offensive line last year, yet the offense ranked fourth in rushing efficiency, according to Football Outsiders' DVOA rankings. In the previous three years, it ranked first twice and seventh once. In 2015, the Seahawks played 11 different offensive line combinations, yet the run game continued to be a strength.

Some will point to individual grades from sites like Pro Football Focus, but the run game is about how the whole operation works together -- the scheming, the blocking and the vision of the back. Thomas Rawls averaged 2.97 yards before contact last season. The only running back in the NFL who posted a better number was Le'Veon Bell. In other words, the run game was working.

Russell Wilson's role in the ground attack cannot be overstated. When the Seahawks line up in the shotgun, defenses have to account for him as a ball carrier on zone-read plays, which is something that has benefited the run game greatly over the years.

2. Pass protection improved noticeably in 2015.

During the bye in Week 9 last season, Seahawks coaches met at the team facility, and at the top of their priority list was to find a way to reduce the number of sacks Wilson was taking. Through the first eight games, Wilson had been sacked on 10.4 percent of his dropbacks, tops in the NFL.

The coaches gave him more options in the quick game, fixed some protection issues and emphasized getting rid of the ball in certain situations (third down, versus the blitz).

In the final eight games, Wilson's sack rate dropped to 4.9 percent. Only seven quarterbacks in the NFL were better at avoiding sacks during that span.

Pass-protection issues doomed the Seahawks early on against the Panthers in the playoff loss, but overall, Wilson had plenty of time in the second half of the year, as he went on a 24-touchdown, one-interception stretch.

3. They're not going to overpay for mediocre talent.

Schneider was asked last week whether he's comfortable with the current state of the offensive line.

"You can look at maybe besides three or four offensive lines throughout the league, it’s a concern for everybody," he said.

In Schneider's mind, demand clearly outweighs supply, which makes for a bad marketplace if you're a buyer. Do you pay up for mediocre talent? Or do you try to develop your own for cheap? The Seahawks have gone with the latter.

According to OverTheCap.com, the Seahawks have about $8.75 million committed to the offensive line in 2016. That's by far the lowest number in the NFL. No other team is at less than $14 million.

In the past, the Seahawks have shown a willingness to gamble on players like Jimmy Graham, Percy Harvin and, to a lesser extent, Cary Williams. But unless they see a true difference-maker, offensive line doesn't appear to be a spot where they're willing to spend a big chunk of their salary cap.

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Overall, behind what most would describe as a mediocre offensive line last season, the offense ranked second in DVOA. From Week 10 on, it averaged 31.25 points per game, second in the NFL.

All of this is not to suggest that Seahawks fans should sit back and feel good about the state of the offensive line. It's the biggest question mark on the team, and it will likely be a major storyline throughout 2016 as the Seahawks try to get back to the Super Bowl after a one-year absence.

It's clear, though, that the organization feels like it has a winning formula with Wilson, an efficient run game and a strong defense. As the weeks go on, if a quality left tackle becomes available, the Seahawks will likely take a look. And they could very well address the need early in the draft.

But last season, the team ranked 30th in spending on the offensive line and still had one of the best offenses in the league. That philosophy could catch up with the Seahawks eventually, but for now, the organization is justifying its stance based on recent results.