Do What U Want and XO.

from 2001 to 2003 britney was banned by clear channe company , brintey company did nut use clear channel to promote her tour

Worst behavior by Drake
XO Beyoncé
TKO Justin
ME Against the Music Britney
Dirrty Xtina
Ashton Martin Music Rick Ross(actually most of Rick Ross singles seem bigger than what they are)
Don't Judge me Chris B
She's a B***h and All n My Grill Missy Elliot
No Matter What People Say and How Many Licks Lil Kim
I Should've Cheated and Love Keyshia Cole
Everything to Me Monica
I Know and Roc Boys by Jay
Hate Me Now and You owe me Nas
Booty Wurk T-pain
One more drink Ludacris

Sing and TKO felt huge.

Where have you been was sort of a flop digitally, Although radio played it to the extreme

Dark Side

Radar by Britney Spears felt huge and I just discovered today that it didn't even enter top 80 in the US or the top 60 in my country

If U Seek Amy also felt massive but it didn't enter the top 10

22 (not a flop, but it underperformed)

Marry The Night + Unconditionally. Both did okay, but flopped compared to the other songs they released.

DWUW and most Britney singles

I'll be Lovin U Long Time by Mariah. I could have swore to Jesus that it was a top 5 song with the way my city's radio stations played it

Run the World, National Anthem, G.U.Y., and Kelis's Bossy all felt like they should've been top ten at the very least. They just had that epic sound.

THIS. All of Kanye's singles after 808s could fit under this description too.

Birthday
Unconditionally
This Is How We Do

I had no idea that I'm A Slave 4 U and Dirrty underperformed until I looked up their peaks.

Peaking low isn't the same as flopping though. Both those songs were really successful, just up against tough comp/sleeper hits