Going into 2013's Thor: The Dark World, Zachary Levi was told the Warriors Three would get more screen time. Levi might be a DC star now, but he started off as a member of the MCU. After being forced to exit the first Thor due to scheduling conflicts, Levi got the chance to play Fandral, one of Thor's best friends, for its sequel. He appeared in just two MCU movies in total: The Dark World, and 2017's Thor: Ragnarok.
Despite the Warriors Three supposedly being a major part of Thor's life, the trio never really made a major splash in the MCU. Tadanobu Asano and Ray Stevenson portrayed the other two members of the group, and together, they all acted as a key support system for Thor. In Thor 2, they helped him break Loki out of prison to save the world from the Dark Elves. It seemed like they would then play a bigger role in Ragnarok, but they were instead unceremoniously killed off by Hela early on.
It's clear Ragnarok must have been a major disappointment for Levi, yet it sounds like that might've begun with Thor 2. During an appearance at Dragon Con 2021 (via The Direct), Levi opened up about his time as Fandral. First, he admitted that he felt the Warriors Three were underutilized in the first Thor, which would've impacted his decision to return for the sequel. What ultimately brought him back was the promise that The Dark World would give the Warriors Three more screen time. Levi said:
“To be honest, I had seen the first one, and I didn’t really feel like The Warriors Three were used all that well, so I was like, ‘Hey, are you going to actually use these folks’… And they said, ‘Oh no, we’re gonna use The Warriors Three a lot in Thor: The Dark World . A lot. Yea, you’re going to be busy.’ And I was like, ‘Okay,’ so I signed up for it.”
Ultimately, the Warriors Three played a bigger role in the first Thor than they did in the second. Thor 2 is often regarded as one of the MCU's few misfires, and it could be argued that one of the biggest issues was its lack of development for the supporting characters. While Thor and even Loki received much attention, those like Fandral and Jane Foster fell to the wayside. At the same time, bits of Thor: The Dark World changed throughout production, so it could be that the Warriors Three did have a larger role at first, only for that to change later.
Fortunately for Levi, he has a much better gig in the DCEU these days. He'll reprise his role as the adult Billy Batson in 2023's Shazam: Fury of the Gods, a movie that is already drumming up a lot of excitement among fans. Levi's time in the Marvel universe is a unique one, having gone from departing a role to returning to it, only to then be killed off with barely a word spoken. Thor 2 might've lured him in with promises of a better story, but it sadly never panned out. At least he's got the superhero role he deserves now.
Source: Dragon Con 2021 (via The Direct)