Because they're superior.

Little Mix has a legit fan base and I feel like Ellie Goulding started out with a core fanbase but she's tried way too hard to become mainstream when the GP does not care for her at all so she lost a lot of her original fans, plus there just aren't a lot of people that interested in her as an artist..... They just use her for "Love Me Like You Do", "Lights", and MAYBE "Burn"

Who is actually a dedicated fan of Ellie Goulding? Not many people, she doesn't really have a huge persona or definable identity.

Because TALENT always wins

There is 4 of them and one of her. And Ellie didn't date anyone famous for visibility...

Delirium was too expensive.

Boh aren't doing well tbh, I love them so it's heartbreaking.

Ellie isn't stannable.

She gets hit singles, but nobody really cares that it's an Ellie Goulding song

Both are talented tbh

The excuses

For LM's standards they're doing extremely well specially in the UK, Ellie not so much

Because Delirium isn't as good as Halcyon.

1+

Wow, I agree with this very true statement.

The 1st one was a joke. But Americans only knew Little Mix through One Direction. You'd have to be delusional not to see that

Perrie and her management obviously saw it, hence why she stuck with Zayn through all the cheating and trapped him with engagement when it was clear that he did not want to settle down.

I'm not buying Delirium because it was $16.99 and the vinyl is like $40 lmao

Ellie tends to fall considerably at first before rebounding, it's the same pattern we've seen with Lights and Delirium (no, I'm not talking about the rereleases).

Little Mix have never booked a major promo platform. Not the AMAs, VMAs or even iHeart Radio. Let's call a spade a spade. Any success they've had outside of the UK is due to their association with One Direction.