The question with Connor would be, if he's clearly that great, how could he fall to 13, let alone to 17 where he ended up going?
Jones had 0 value to the Kings. He was a RFA that wasn't going to sign, the Kings were up against the cap, and weren't going to pay a backup $3m per year. Sure, trade Quick instead. To who, and for what? What else do you have to give up, when other teams are fully aware that Lombardi is up against the cap, and looking to trade the more expensive of the two goalies?
And each came about because of Voynov. Who knows how 14-15 goes if Voynov doesn't get suspended. Who knows if that 1st is moved, and if it still was, maybe it's not for Sekera.
They went on a streak, and were still basically the same can't be killed Kings at the time. Get a defenseman to replace Voynov, and who knows. Then Sekera got hurt, the can't be killed Kings couldn't win a must win game against the Oilers, and the season goes down the toilet.
Then, because the 2016 1st was traded for Sekera, you can't miss the playoffs, and then maybe miss the playoffs the next year, giving Carolina a potential lottery winning pick. So Lucic comes aboard. Jones had no value to the Kings, and you weren't going to get Lucic at 50% for Miller/1st alone, so Boston also gets one or the other out of the deal too.
Voynov is what effectively closed the window. Now Kopitar has a bigger contract, which will mean some player can't be kept/brought in. Brown is another year into disappointment. There are no proven young right handed defensemen on good contracts who can keep the window open right now that the Kings can get. Gaborik and Carter are another year older. Toffoli is also that much closer to his own bigger contract, which will mean yet another player can't be kept/brought in.