Not one of the downvoters, but working in (hundreds of) centimetres (240cm) as opposed to meters (2.4m) is not as crazy as it sounds. Tape measures or carpenter's rulers will have centimetres on them all the way.

Also, people consider it a matter of precision. If I ask for a piece of wood that's 2.4m long, I am probably less concerned with the precise length than if I ask for one that's 2400mm long.