The Kings have actually made the right draft pick in virtually every draft, the players just aren't good enough.
The Kings may or may not draft well, but they make really stupid trades. There is some question as to how much of the blame can be assigned to Geoff Petrie and how much of the Kings' problems have to do with bad ownership.
last few trades (acquired first)
Hickson for Casspi & protected 1st - seems like a good trade, especially at the time
Fredette & Salmons for Biyombo & Udrih - not a bad trade, but not great
Daniels & cash for 2017 2nd (needed dollars for salary cap)
Thornton & cash for Landry - good trade
Taylor & cash for 2011 2nd - no real impact either way, but they got cash
Jackson & 2011 2nd for Brockman - no real impact either way, but they got cash & a pick in the process
Dalembert for Nocioni & Hawes - improved team short term & got out of Nocioni, but Hawes is a solid young player
Landry, Dorsey, Hughes, cash for Martin, Armstrong, Rodriguez - Martin was keeping them from being really bad and they got some nice young pieces, but overall a poor trade
Armstrong & cash for 2016 cond. 2nd - no real impact either way, but they got cash
Rodriguez, Brockman, & cash for Pendergraph - great trade
Solomon & cash for 2014 cond. 2nd - no real impact either way, but they got cash
McCants & Booth for Williams & Brown - no real impact
Diogu & cash for Ruffin - good trade
Nocioni, Gooden, Ruffin, & Simmons for Miller & Salmons - ok trade
Cassell & cash for 2015 protected 2nd - good trade
Jackson, Green, protected 1st (casspi), cash for Artest, Singletary, Ewing Jr. - good trade for where team was at
That takes you through the free agency period of 2008 to the present (oldest first). Overall Martin was the only really poor trade, most of the others had no real impact, but probably lean towards the good end of the spectrum. The reality is, Sacramento is just stuck in no mans land. They aren't good enough to make the playoffs, but they aren't bad enough to be really terrible and land the franchise player in the draft (and haven't hit in the lottery either).