"You're constantly evaluating; the job you're doing, looking at moves that we made, moves we could have done better or done differently," Preller told MLB.com on Tuesday, before the Padres faced the Pirates at PNC Park.
"I've done that more than anyone."
The Padres entered play Tuesday with a 39-46 record, a season-high seven games below .500 and 8 1/2 games behind the first-place Dodgers in the National League West.
To be sure, this wasn't at all what Preller had in mind when he revamped the team during a frenetic winter.
Preller, after all, made a bevy of noteworthy trades in December -- adding outfielders Wil Myers, Matt Kemp and Justin Upton, among others -- then signing free agent pitcher James Shields to the largest contract in club history before adding closer Craig Kimbrel less than 24 hours before Opening Day.
So, what happened?
"I think it's been the ability to consistently put all the pieces together -- offense, defense and the pitching. That's the part we haven't done a very good job of in the first half of the season," Preller said.
"We had moments early where the offense carried us. There have been moments of late where the bullpen and pitching has been good. That's why we're where we are at."
The Padres have been shut out 13 times this season and their .239 team batting average ranks 14th out of 15 National League teams. The team dismissed longtime manager Bud Black on June 15 and has gone 7-13 since, 7-12 under interim manager Pat Murphy.
Kemp entered Tuesday hitting .239 with six home runs. Upton, the team's lone All-Star, leads the team with 14 home runs, but has hit .190 since June 1. Myers, one of the few bright spots, offensively, played in 35 games before needing surgery on his left wrist last month.
The pitching was a variable early, but has been better of late. The pitching staff has allowed the most unearned runs (46) in baseball because of defensive missteps, an area perceived to be a concern before the season began.
"I think we know we're capable of playing better, whether that's the production from Matt [Kemp] and some of the guys offensively or elsewhere," Preller said. "I think some of the starting pitchers who were giving up the long ball early have sort of righted the ship.
"I think overall, being seven under .500 or wherever it ends up at the All-Star break, everyone's disappointed in the clubhouse. I think we expected to play better baseball than that."
In terms of the success of many of the players Preller dealt away -- Cameron Maybin in Atlanta, Joe Ross, who made his Major League debut with the Nationals last month, and shortstop Trea Turner, now in Triple-A with the Nationals -- he's not concerned with that.
"There are going to be players go elsewhere and have some success. But we're looking more at our shop and how we can do things better on our end," Preller said. "We knew when we moved some of these guys we'd look up and see them having some success.
"The focus on our end is how can we get our guys to have that type of success?"
Murphy, brought up from Triple-A El Paso, has tinkered with the lineup. He had Kemp hit in the leadoff spot recently. Catcher Derek Norris did so on Monday and Tuesday.
As for what the rest of July holds -- with the non-waiver Trade Deadline looming on July 31 -- Preller said the organization is in full evaluation mode in case they decide to sell or buy. Upton and starting pitcher Ian Kennedy are two notable players who will be free agents after the season and figure to be attractive pieces to other teams.
"I think it's that type of year where you're evaluating and the focus is on being prepared for the next three weeks and being prepared for different scenarios," Preller said. "It's not a record thing from our standpoint, but what the value is on the market, if we think there's going to be good deals, whether that's adding to the club or changing the look of the club a little bit, that's what this time of year is for. We're still in the process of evaluating that."