Their bullpen ERA was still in the bottom half of the league. They weren't as bad as in 2014 but they weren't good and sure as hell could use someone like Madson or O'Day.
Though they struck out more (26.1% to 22.3%) and walked fewer (7.6% to 9.9%) than they had in 2014, an inflated home run per nine rate (.98 up from .70) and a higher BABIP (.317 from .293) led to pretty similar run prevention (3.91 up from 3.80).
The underlying numbers show their ERA likely should have been better. The increased BABIP hurt. The increased HR/9 hurt (although, that could be due to the fly ball tendencies of pitchers like Garcia, and to a lesser extent, Baez -- however, it's impossible to say whether or not that will carry over to next season). They still have the high K/low BB guys that contributed to the strong numbers in those categories last year (Garcia, Baez, Jansen, Hatcher).
Also on point:
[T]hey’ve already excised the biggest problems. Jim Johnson is long gone. Guys like Chin-hui Tsao, Eric Surkamp, Sergio Santos, etc., who all contributed to the overall season line won’t be back.
They have some promising young pitchers in the minors who could contribute to the bullpen in the second half next season (Jharel Cotton, Jose De Leon, Julio Urias, etc.).
Further, had the 4th worst inherited-runners-scored percentage, which appears to be a volatile statistic subject to fluctuation from year to year (
http://dodgers.mlblogs.com/2015/12/04/dodger-relievers-can-once-again-be-grand-at-the-strand/).
They're really not in as bad of a spot as people think. Would it be nice if they added an elite reliever? Of course, most teams would like that.