The New York Mets and Los Angeles Dodgers both just spent dearly to upgrade their bullpens, overpaying two competent but hardly elite relievers with three-year deals that don't seem to reflect those relievers' performances or the current imbalance of oversupply and insufficient demand in the marketplace.
The Mets already traded their top two prospects (Jarred Kelenic and Justin Dunn) for 36-year-old Robinson Cano and an elite reliever in Edwin Diaz, and even that entails a ton of risk given how often relievers break down or fail to hold their performance year over year. They might argue that adding Jeurys Familia provides them with a failsafe in case Diaz isn't as good in 2019 as he was this past year, but this is a commitment you might make to just one reliever, the one you intend to use most in high-leverage situations.