So the story with Beal, as I understand it, is he got the Supermax a couple years back when he made All-NBA became eligible for it. That was also the year he won the scoring title. So he negotiated the supermax extension with a NTC, in exchange for signing the early extension as Washington had plans of building a contender around him and the supermax showed he was locked in for like 6 years and the trade clause was showing how player friendly they were. This was all done by the previous regime, who was then fired a little while later because they sucked and didn't make any moves to bring anyone in. Plus the previous front office were also the guys who gave Bertrans big money, so they weren't exactly smart with extensions or contracts. They sucked again this year and ownership having a new front office in place gave them the go ahead for a full rebuild. Tough to do that with a 29 year old Beal owed $50+ million a year for 5 years so they needed to deal him. Miami reportedly offered 2 1st round picks with Duncan Robinson and Kyle Lowry. Beal catches wind of Phoenix offer and says no to Miami he wants Phoenix but only if it's the deal for CP3 and he no longer is ok with Miami either. So he had them at his mercy. He played 2 front offices in Washington.
Washington fans have said they wish the front office held him ransom since they got so little, basically nothing. Of course that wasnt going to happen but Im surprised they didn't try calling Beal's hand and rolling him out with a bunch of scrubs and rookies but then, that's essentially been what they've done anyways. Washington now plans on becoming the OKC of the East, taking bad contracts for picks and helping facilitate moves for assets. They know they won't compete and happy, kind of, to have a direction. They seem Sarver-esque.
TLDR - Beal screwed Washington multiple times, in a roundabout way and then more directly. Supermax's are bad, so are NTC, and Supermax's with NTC's means that player now has the franchise at their mercy.