in for an inch, in for a mile
- (chiefly US) Given that one is partly involved in or committed to a project, action, position, etc., there is no reason to refrain from becoming fully involved or fully committed.
2005, Bill Burt, William D. Burt, The Downs, →ISBN, page 29:Afterwards, she took him farther south. His uneasiness grew with every step. . . . "In for an inch, in for a mile," he muttered.
2007 December 31, Maggie Petsch, “American oystercatcher shots are memorable”, in Daily News, Galveston, Texas, retrieved 16 July 2009:I soon found the water lapping at my toes so I figured, “in for an inch, in for a mile” and continued on in after the oystercatcher.