Golden State has become a dynasty with three titles in four years. But extending it into the future is no sure thing. (Kyle Terada/USA Today)

With the NBA playoffs behind us, The Washington Post’s Tim Bontemps will analyze the biggest question facing each playoff team as it enters the offseason. Next up are the two-time champion Golden State Warriors, who have been accused of ruining the NBA as they become its latest dynasty. But will their reign atop the NBA continue indefinitely?

There have been plenty of pronouncements that the burgeoning Warriors dynasty has ruined the NBA, after Golden State completed a sweep of the Cleveland Cavaliers in the NBA Finals last week to win its second straight championship and third in four years.

The Warriors feel differently, though. And even as he was drenched in some of the $400,000 worth of champagne he bought for his team to celebrate its latest triumph early Saturday morning, Golden State owner Joe Lacob was loudly dispelling the notion that the Warriors can rest on their laurels.

“We certainly are going to try to improve our team,” Lacob said. “That, I can guarantee you. We will do everything we can to improve our team, because the competition is getting better every year.

“Houston made a big leap this year. Boston, Philadelphia … they’re coming. Maybe other teams. So we have to stay ahead of them.”

Lacob has a tendency to be a bit hyperbolic, but he is correct here.

Golden State is undoubtedly the league’s best team. But the Warriors are not invincible, evident in both Games 6 and 7 of the Western Conference finals, when they trailed the Houston Rockets at halftime.

There weren’t many claims of a lack of competitive balance to be heard then.

And if the Warriors want to remain ahead of the pack, make it to a fifth straight NBA Finals and win a fourth title in five years — something not done since Bill Russell’s Boston Celtics ruled the league in the 1960s — significant changes will have to be made.

We’ll get to the changes in a minute, but first, let’s examine the challengers. Houston remains a significant threat. But there is an argument to be made that this was the Rockets’ best chance to dethrone the Warriors, with Houston’s core players all either in their prime or hitting the end of it as they move into their early 30s.

But if there is a single general manager in the NBA who can be entrusted with continuing to be aggressive, it is Houston’s Daryl Morey. After getting Chris Paul last summer, don’t be surprised if Morey has another ace up his sleeve this summer.

Then there is the competition out East. As Lacob himself referenced, both the Celtics and Philadelphia 76ers are on the rise. Boston made it to the seventh game of the Eastern Conference finals this year despite not having Kyrie Irving or Gordon Hayward for the entirety of the postseason; add both to the current team, and Boston easily has enough firepower to make it out of the East and give Golden State a run for its money.

Philadelphia, on the other hand, not only has two of the best young players in the NBA, Ben Simmons and Joel Embiid, but also the cap space to sign a max player — plus the trade assets to go get another, if they so desire. Sure, there are things that could complicate the Sixers’ trajectory, from Simmons’s lack of a jumper to Embiid’s health to whatever happened to Markelle Fultz this season. But from a pure talent standpoint, few teams can rival Philadelphia long-term.

Then, of course, there is LeBron James. Cleveland didn’t have the horses to compete with Golden State in the Finals, but now James has the chance to survey his plentiful options, from staying in Cleveland to going to Houston, Philadelphia or elsewhere. If he does choose to leave, going to the Los Angeles Lakers stands out as the most likely destination.

Say James gets Paul George to sign there with him this summer. Then the Lakers could take their pile of young players — namely Lonzo Ball, Brandon Ingram and Kyle Kuzma — and go chasing after a third star. Perhaps Kawhi Leonard, if he doesn’t come to an agreement to stay in San Antonio. Or Damian Lillard, who not only has been said to have caught James’s eye in the past as a potential playing partner who could resemble what Kyrie Irving was next to him in Cleveland, but currently plays on a Portland team that’s stuck in salary cap hell.

Regardless: Golden State does not remain, as Lacob once infamously said, light-years ahead of the league. Moves will have to be made this summer by General Manager Bob Myers to keep them out in front.

Andre Iguodala’s injury during the playoffs — and how bad the Warriors looked without him — exposed the weaknesses of their roster outside of its top-level talent, especially on the wing. Nick Young and Omri Casspi were complete failures, and Patrick McCaw regressed before getting injured and basically missing the postseason.

No wonder Warriors Coach Steve Kerr openly talked about the importance of the team’s first-round pick — No. 28 overall — saying he’d have to play whomever the Warriors select.

“I think it’s a big deal,” Kerr said. “Having talked to our scouts … they like the pick. They think we are going to get an impact player, and I think I’m going to play that guy and give them a chance, given the state of our team.”

Luckily for Golden State, there are several wing players that should be available in that range — from Villanova’s Donte DiVincenzo to Duke’s Grayson Allen to Cincinnati’s Jacob Evans to Tulane’s Melvin Frazier to Creighton’s Khyri Thomas, among others — who could step in and contribute right away.

More development will be needed from rookie big man Jordan Bell, too. The same goes for Damian Jones, who didn’t play his first two seasons. Golden State hopes to bring back Kevon Looney and McCaw, but both could get bigger free agent offers elsewhere.

Factor in the amount of complacency and boredom that set in for the Warriors this season, plus wear and tear on their four stars — all of them missed at least nine games, including 37 absences for Curry, while Green’s shot went south of the equator as he dealt with shoulder issues all season — and there’s enough doubt here to make rubber stamping Golden State’s dominance for the next five years a fool’s errand.

Kerr even went so far as to say he’ll have to focus on the “game within the game” next season to try to keep his team motivated for yet another two-month long playoff run. There’s a reason, after all, no team has made it to five straight Finals, or won four titles in five years, in 50 years.

“They’re coming for us,” Myers said. “It’s not just, everybody references Houston, but there’s a lot of good teams in the NBA.

“It’s going to be harder. I don’t know how it will end up, but I know it will be harder. Hopefully we’ll be in the same spot next year, but we’ll see.”

More NBA Postmortems:

Game 7 proved the Rockets need to target another shooter this summer.

The Philadelphia 76ers should go after Paul George, not LeBron James.

Will DeMarcus Cousins be back with the New Orleans Pelicans?

After another demolition at the hands of the Cavaliers, what’s next for the Raptors?

The Milwaukee Bucks need a new coach. They can’t afford to pass on Mike Budenholzer.

Playoff exit is likely just the beginning of a painful summer for the Oklahoma City Thunder

The Miami Heat bet big on Hassan Whiteside. It appears they made a mistake. Now what?

After first-round sweep, Blazers’ next steps could include trading away their stars