Her birth name, G.L.O.R.I.A. T.A.N.G., stands for something much more perverse…

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[5.75]

Iain Mew: Her name stands for Get Everybody Moving. It’s difficult to see what movement this could induce other than a clumsy stomp, but its utterly direct blast of fury has a certain undeniable power.
[6]

Patrick St. Michel: This has nothing to do with the song in question, but I just love the fact G.E.M. does something called a “Work Experience Tour,” which involves her swapping jobs with someone once a month. So far, she’s been a shop assistant, a domestic worker and a professional motocross rider. Oh yeah, “What Have U Done”: the verses sound like the typical attempts at “rocking out,” with the appropriate amount of energy that comes from such canned efforts. The chorus, though, allows her to show off her voice, which turns out to be way more compelling than any guitar chug found on this song.
[6]

Anthony Easton: It’s kind of generic, and not nearly as angry as it could be, and the question seems rhetorical, but not rhetorical in any sort of emotional way.
[4]

Brad Shoup: When I hear the unclenching of electric guitar on a new single these days, I wonder which I’m about to hear: Asian pop or American country? I’m uncertain that we’re hearing the fullness of the Young Empress of Heaven with Giant Lungs, although she puts a wonderful ferocity into the title question — I don’t know that I’ve consciously heard it in song before, but I want more. The track is a fine pop-metal distillation: strutting and flanging, kicking you up and down the sidewalk.
[7]

Alfred Soto: I love the guitar underpinning the urgency of that call and response chorus. Promotional dollars still couldn’t get this up the charts next to Katy Perry.
[6]

Will Adams: The most edge comes from the turbulent but bracing shifts between 6/8 and 12/8 in the intro, but what follows is a load of aggression without anything behind it. The faux-rawk synth stomp is running on a half-empty tank, dulling the title’s barb even more than G.E.M.’s strained high notes did. 
[4]

Alex Ostroff: Glam-metal-schaffel à la Born This Way, but more generic. The downside is that there’s nothing as idiosyncratically brilliant as “Scheiße”. The upside is that there’s nothing as idiosyncratically stupid as ‘Judas’.
[6]

Jonathan Bogart: Closer to Kelly Clarkson’s pop-dressing-up-as-rock exercises than anything meant to convince you of its chug and thrash, it similarly relies on G.E.M.’s powerful voice to wrench emotional meaning out of sculpted plastic.
[7]