Thomas Sweeney's first incentive to become a line judge was the offer of a free sandwich.
For Pauline Eyre, who called the lines at Wimbledon for 16 years, some natty blazers and the chance to buy tickets for the tournament were the main recompense for work she had to take annual leave to do.
Nowadays the best officials might earn up to £200 a day plus expenses.
But line judging has never been about the money for those who spend hours leaning forward, hands resting on knees, staring intently at a line of chalk to determine in a split second on which side of it the yellow ball has bounced.