100% Vote-By Mail more problematic than absentee systems

Absentee systems are limited in nature. Those that need ballots for a reason remotely, get the ballot absentee. This system is easier to deal with, in short, because it is a smaller system. Turn absentee voting into liberalized, no-excuse, Vote-by Mail voting and the problems are amplified.

Therefore Vote-by Mail inherently has more problems than limited absentee voting systems. For more, read this.