I would imagine that since paper money gets its value entirely from the trust the public places in its authenticity and value, any printing defect will cause ch

I would imagine that since paper money gets its value entirely from the trust the public places in its authenticity and value, any printing defect will cause chaos when the not-completely-uniform bills go into circulation. This will waste the time of those that need to check for authenticity (imagine the image scanners that need to be adjusted for this), deflate trust in what constitutes an authentic bill, and devalue the "defect" currency as it may not be accepted in all scenarios.