Every owner/GM needs to gamble for a team to succeed. Hindsight is always 20/20, but the truth is that every transaction is a risky move until proven worth. Freak accidents, team chemistry issues, etc are all factors you can’t measure before a trade/signing. Off the top of my head, rookie Kobe for Vlade was one of the biggest payoffs in NBA history (as for “riskiest” move, that is up for debate)
Darko is one of the greatest “don’t draft based on position if you have a top-5 pick” examples in NBA history.
Wade and Bosh are more revisionist history (though obviously had HOF careers), but passing up Melo?
Pistons left a lot of money on the table.