WHY are pop songs popular? It’s a question many of us have an opinion on.

“There is a beautiful vocalist wearing not much”, “the tune is bright and upbeat”, “It’s all down to the marketing team”, “It gets played national radio so it’s bound to do well.”

These certainly might play a role but a team of psychologists from the University of Southern California, led by Professor Andrea Ordanini, have come to another conclusion - it’s all about repetition.

Now, this is nothing new. We’ve all experienced that nice feeling when we are listening to a record and recognise the motif from the first verse. It’s often what good songwriting is based on.

But what Prof Ordanini is saying is that the number of times the actual chorus is repeated is directly proportional to its success. They worked out that the chances of a track making it to number one increased by 14.5% each with each repetition.

Ordanini said: “For many of us the songs that stand out in our minds are those in which we can easily hear the same words repeating themselves over and over again in our heads.”

But why is this?

According to the research in the Journal of Consumer Psychology it’s due to the fact that our brains can process them more quickly - little bit like cookies stored your computer system that help webpages appear more quickly second time round.

2 Unlimited's No Limit incredibly did not make the cut

To find this out they listened to thousands of songs from the last six decades (nice excuse!) and compared those who got to number one with those who never made it into the top 90.

Recognise any of the below? They are the two most repetitive number one songs per decade with a chorus repeated seven times or more - a notable exception from the list being 2 Unlimited’s 90s classic ‘No Limit’.

1960s 

Marty Robbins - El Paso

Zager and Evans - In The Year 2525 (Exordium and Terminus)

1970s

Ringo Starr - Photograph

Bee Gees - Jive Talkin’

1980s

USA For Africa - We Are The World

Tears for Fears - Shout

1990s

Amy Grant - Baby, Baby

Notorious B.I.G. - Hypnotize

2000s

Usher - U Remind Me

Jennifer Lopez - I’m Real

2010s

Rihanna - S&M

Adele - Set Fire To The Rain