It means even the grandest project depends on the success of the smallest components. It is a variation of 'God is in the details', meaning whatever one does should be done thoroughly, because details are important. This positive version is generally attributed to the French writer Gustave Flaubert. Other attributions include Michelangelo or the architects Le Corbusier and Mies van der Rohe. 'Governing is in the details'' and 'The truth, if it exists, is in the details' are recent variants.

Übersetzung:

der Teufel steckt im Detail

Gegenteil(e)

The opposite of "the devil is in the details" is "to ignore the details and go from the particular to the general".

Synonym(e):

You could also say: the hard part of what someone is trying to do is in the many small details.