Shipway,
There isn't a struggle to find people who WANT to be ATCO's there's a struggle to find suitable qualified people with the right temperament and aptitude who can go on to validate. I am no HR expert but personality plays a big part in becoming an ATCO at many stages. If you're serious about it, learn from it and prepare yourself ready for next time. Many people who are now valid were successful on 2nd and 3rd attempts.