For Milwaukee, this deal is all about shedding some salary. They gain around $3 million in cap space by swapping Dellavedova for Williams. Plus, they no longer owe a guaranteed salary to their pick at 17, and instead have a non-guaranteed contract at 31. Williams gives them a rebounding big man who can score off the pick and roll. He also gives them a bit more cap room to re-sign Jabari Parker and any other mid-level free agents they’d look at to try and bolster their roster.
For the Suns, they get the 17th pick to pair with the 16th pick, in hopes they can package the two together with other assets to get another lottery pick in this draft. They also get a crafty, veteran point guard who is good defensively and is a good teammate, two things the Suns need going forward. If they are able to trade 16 and 17, taking on the extra salary will be worth it.