This comment was made by the writers of the history of the Wolseley Motor Company about the Great War. During that conflict a great many mechanical engineers joined the Army Ordnance Department who had responsibility for maintaining all weapons or the Army Service Corps which handled all mechanical vehicles. The tank came somewhere in between, maintained in the great central workshop at Erin in France.
One of the huge challenges in the Great War was that skilled men were joining up and being sent to the trenches in their thousands with their skills ignored. It took the initiative of Lloyd George to ensure that skilled men were either directed to the armaments factories at home or in the AOD in the field.
In the interwar period, vehicles were added to the remit of the then RAOC and this included the creation of the Army Centre for Mechanisation at Chilwell.
In 1942 there was growing concern within the army that men skilled in engineering were disbursed too widely in the RAOC, RASC and Royal Engineers and that is would be far more efficient to bring them together in a single Corps. In the words of the Committee's report:
Until the Army gives to mechanical and electrical engineers, as distinct from civil engineers, their appropriate place and influence in the Army system, such engineers are not likely to be caught, tested and trained as well as in the Navy; there is a danger that they will be missed by men who main interests and duties lie in other fields.
It was in this way that REME came into being.
You can read more about the mechanisation of the army in WW2 in War on Wheels and about how the army was equipped for the Great War in Ordnance. I explore further the story behind the formation of REME in Dunkirk to D Day.