A sample of nearly 200 players, aged between 13-18, also revealed only six per cent of the budding ballers even go on to play in lower leagues.
The University of Essex researchers discovered the players who succeeded excelled in self-confidence, ball reception skills, dribbling and coaches’ subjective technical assessments.
The study – published in the International Journal of Sports Science & Coaching - looked at players within the academy system in the 2009-2011 cohort and then traced their progress 10 years after their final academy test.
Elite academies
Dr Jason Moran, from the School of Sport, Rehabilitation, and Exercise Sciences, looked at elite Spanish academies for two LaLiga teams in Madrid, over the course of 10 years.
It is one of the most watched club competitions in the world - featuring the like of FC Barcelona, Real Madrid, and Villareal - and reaches 2.8billion people globally.
It is hoped the research will shine a light on the implications and economics of the academies amid the high-profile closure and re-opening of English Premier League side Brentford FC.
Crossroads
Dr Moran said: “This leaves us at a crossroads in terms of the role of the modern football academy.
“As many as 95% of teenage players aren’t ‘making it’ to pro football, yet they are continuing through these academies incurring the stresses and strains that go with intensive professional training, before they are eventually deselected.
“The question must therefore be asked if academies are providing appropriate developmental experiences for the large proportion of players who are deselected from their systems?
“This relates to anything from physical literacy, to educational initiatives to prepare for life post-football.”
Less-developed athletes
It also emerged none of the players who ran out professional sides were born in the last quarter of the year and 44% of all the academy players were born in January, February, or March.
Meaning coaches may have a bias against smaller less-developed athletes who are technically sound.
Of the 12 players who became professionals, seven reached Spain's highest professional league at some point in the decade.
Five also played for teams in Spain's second highest professional league and four played abroad.
Previous studies on Premier League academies have shown just one per cent of under-nine players make it to the top tier.