"Defailance" is a word in ENGLISH

The act of disappointing, or the state of being disappointed; defeat or failure of expectation or hope; miscarriage of design …

Miscarriage; failure; deficiency; fault; -- mostly superseded by failure or failing, except in the phrase without fail.

Failure of success when on the point of attainment; defeat; frustration; miscarriage.

Unfortunate event or issue of an undertaking; failure to attain a desired result or reach a destination.