2. DeMarcus Cousins
The Warriors entered the 2010 NBA Draft with the sixth overall pick after Stephen Curry's rookie season had resulted in a 26-56 record and 13th-place finish in the Western Conference.
Golden State wanted to find their center for the future, but unfortunately they missed out on getting the best one available by one solitary pick. The Sacramento Kings took DeMarcus Cousins with the fifth selection, leaving the Warriors to take Ekpe Udoh at six.
Udoh played 96 games for the franchise in less than two seasons before being traded, along with Monta Ellis and Kwame Brown, for Andrew Bogut and Stephen Jackson (who would never play a game in his second stint with Golden State).
Bogut proved a huge piece for the Warriors, so Udoh play his part to some degree. However, he would go on to average just 3.5 points and 2.9 rebounds in 384 career games for four different teams.
In contrast, Cousins became a four-time All-Star and two-time All-NBA selection. While he was never the defender Bogut was in his time with Golden State, adding Cousins' versatile offensive skillset alongside Curry (and with Thompson and Green to come in following drafts) would have been a nightmare for opposing teams. It seems the regret may not just be on the Warriors' side either, with Cousins revealing in 2022 that he wished he skipped his workout with the Kings before the draft.
"What did Sac do for me? Besides say my name (draft day). I did more for them than they did for me. That's just being honest."DeMarcus Cousins
Cousins would sensationally join the Warriors in a league-shattering free agency move in 2019, but he was coming off a torn achilles and was ultimately never the same again. He played 30 games for Golden State and an addition eight in the postseason, including a trip to the 2019 NBA Finals.