Grey area on black-and-white subject

Among the many readers’ queries I receive and do my best to answer is this difficult one: why is a chequered flag used for ending races?

I suppose a chequered flag is used for the finish of a race because other flags of various colours are in use for different circumstances during a race and a chequered one is easy for drivers to see. Not that this shouldn’t apply to emergency flags, but there it is

I believe it was originally specified that the finish flag should be waved at the winner, then be held stationary as the remaining finishers went past it, but this may now not be kept to. There is also the conundrum about race-starting flags. I believe `Ebby’ at Brooklands once used a red one but later, quite rightly, the national flag was used.