2. Trying to outscore everybody
When the Suns went and got Beal, the assumption was that they could have the best offensive rating in the history of the league by the end of the season. Instead they finished a respectable 10th (116.8), which would have been fine if their entire identity wasn't built around blasting opponents away with sheer firepower.
Finishing sixth in made 3-pointers each night (36.5 percent) was also nice, but that had as much to do with Grayson Allen leading the league in this area than anything else. The problem with all of this though, was that the group had no Plan B if they had an off night offensively. Which shouldn't have happened, but did for a number of reasons.
The most important of which was Beal missing a good chunk of the first half of the season through injury, while Booker trying to figure out how to be more of a facilitator didn't help either. On nights when Durant didn't have it - which admittedly was not all that often - and the Suns had to grind out an ugly win, they just couldn't get it done.
This again ties into Nurkic - as for all of the nice passing out of the post and offensive creativity inside the paint he provided - defensively he just is not near the level needed to close out opponents. So when the Suns needed to shut up shop or try and find a different way to win, they simply didn't have it. That can't happen again under coach Budenholzer's watch.