The evident way to view the three-sided trade between the Boston Red Sox, Kansas City Royals and New York Mets that sends outfielder Andrew Benintendi to Kansas City is that the Red Sox don't believe Benintendi will return to the heights he reached in 2018, while the Royals are willing to spend more than $6 million because they believe he can.
The other parts in the trade are not of zero value -- the Red Sox get tooled-up outfielder Franchy Cordero from the Royals and minor league pitcher Josh Winckowski from the Mets, and there are some players to be named later going to Boston and the Mets -- but this is mostly about the Red Sox trading Benintendi's $6.6 million salary.