A season after winning their first title in 108 years, the Chicago Cubs couldn’t recapture that same magic in 2017. They started off slow, suffering one of the worst hangovers ever for a defending champ, and struggled to fend off the upstart Milwaukee Brewers for most of the summer. Although Chicago did eventually start playing to its potential in the second half of the year, the Cubs needed an epic Washington Nationals meltdown (and maybe a little help from the umpires) to squeak their way into the NLCS, where they rarely seemed like fair competition for the Los Angeles Dodgers. It took five games for L.A. to officially end Chicago’s repeat bid, with the Dodgers winning 11-1 at Wrigley Field on Thursday night to finish the series.Now Theo Epstein, Joe Maddon and the rest of the Cubs’ brain trust have five months to contemplate what went wrong in their team’s title defense.They can start by looking at the bullpen, which blew game after game. One of the Cubs’ prize trade-deadline additions, reliever Justin Wilson, pitched only 0.2 innings in October, and many of Chicago’s other bullpen arms disappointed. Epstein was never able to assemble the stocked relief cabinet that other top playoff contenders, from the Dodgers to the Yankees, managed to collect.But there’s plenty of blame to go around. The Cubs’ usually dynamic duo of Anthony Rizzo and Kris Bryant scuffled, and the whole lineup produced one of the worst offensive performances in the playoffs in decades. And in general, this roster wasn’t as talented as the one that steamrolled the league in 2016. Although a healthy Kyle Schwarber, who returned this season after missing all but two games last year with a torn ACL, should have offset the loss of Dexter Fowler, the returning slugger never hit as well as expected, and the offense took a small step back. On the other side of the ball, the Cubs’ incredible pitching and defensive performance last season fell back down to earth in 2017.Even Maddon, who has a reputation as a tactical genius, showed signs that his strategic brilliance may be only skin deep. In the ninth inning of Game 2, Maddon made the controversial decision not to use ace closer Wade Davis, instead opting to hand the ball to starter-turned-postseason-reliever John Lackey, who had also pitched the night before — and the results were predictably disastrous. Lackey proceeded to give up a walk-off dinger to Dodgers third baseman Justin Turner, putting the Cubs in an 0-2 series hole from which they never recovered.On its own, Maddon’s decision wasn’t as egregious as, for example, Orioles manager Buck Showalter sitting Zach Britton in the Wild Card contest last year. But it’s part of a pattern of less-than-stellar bullpen management for the Cubs skipper. Last season, Rian Watt and I created a bullpen-management statistic with which to grade managers, and Maddon has been surprisingly mediocre — 22nd out of 35 qualified skippers — in that aspect of the game over the past several years. (In fact, Maddon’s score was almost identical to Showalter’s.)Other managerial metrics are similarly unkind to Maddon: He has often ranked highly in former Grantland writer Ben Lindbergh’s managerial meddling index, which quantifies the degree to which coaches call for often-unwise tactics from the bench. So perhaps it was fitting that Merlot Joe’s reliever usage wasn’t the only questionable call he made this October. As sabermetrician Dave Cameron pointed out, Maddon’s calls — including setting the lineup and failing to pinch hit in several tight spots — were poor throughout Game 2.This isn’t to say that Maddon is a bad manager. Despite the outsized importance that bullpen decisions acquire in the postseason, we found that they only tend to be worth a win or so over the full season. How a skipper manages his players’ egos and clubhouse chemistry is likely to be much more important than the fiddling he does with a lineup or the pitcher he calls on to get critical outs. And Maddon excels in those soft skills: He is famous for maintaining a relaxed, jovial clubhouse, and it shows in the outstanding performances of his players.But this season, Maddon was unable to coax quite enough out of his roster. There is good news for Cubs fans: Several of the All-Stars from last season’s World Series-winning outfit will return again next year. Since the difference between the wild card winner and the World Series champion often comes down to luck, the Cubs might only have to wait until next year — instead of 107 years from now — before they celebrate once again.