Over the last 15 years, the Marvel Cinematic Universe has proven single-handedly responsible for popularising credits scenes which both tee up future entries into a given movie franchise and also deliver some fun, consequence-free gags for those who bother to stick around.
Many of the MCU's credits scenes have of course paid off in spectacular fashion - most notably Thanos' debut at the end of The Avengers - but with the franchise now counting more than 30 films to its number, it'd be unreasonable to expect every credits scene to directly lead to something major.
All the same, there are a number of credits scenes which clearly seemed to be setting something else up, and yet to date we've not seen them followed up on at all.
In some cases it's clear that creative plans changed and we may well never see these scenes resolved, while in others it's just a case of timing and waiting patiently for them to eventually be addressed.
Whatever the reason, fans have been waiting for years, perhaps even a whole damn decade, to see these credits scene go somewhere worthwhile...
10. Harry Styles Is Thanos' Brother, Eros - Eternals
Eternals' head-scratcher of a mid-credits scene saw Thena (Angelina Jolie), Makkari (Lauren Ridloff), and Druig (Barry Keoghan) cross paths with Pip the Troll (Patton Oswalt), who soon enough introduced them to Thanos' (Josh Brolin) brother Eros aka Starfox (Harry Styles).
Eros reveals that he knows where the other Eternals kidnapped by Arishem are, and wants to help get them back. Cut to black.
The scene quickly became infamous upon release due to the undeniable stunt casting of Harry Styles in the role of Eros, but considering that he's playing Thanos' brother and offers a helping hand to the heroes, it felt like it was pointedly setting up future adventures featuring the character.
It's been 18 months since Eternals' release, however, and we're heard not a peep from Eros since.
This may be in part due to Eternals under-performing both critically and commercially, yet last summer Kevin Feige nevertheless confirmed that there were future plans for both Eros and Pip, without elaborating further.
Short of Eternals 2 actually happening - which seems incredibly unlikely - it's surely far more probable that the duo will show up as supporting players in somebody else's movie or Disney+ series. But to date, there's been no follow-up whatsoever.