Introduction of electronic voting in the US was primarily motivated by the Help America Vote Act of 2002 which required that election authorities more effectively accommodate the needs of voters with sensory and mobility needs. Previously used election methods were generally inoperable by individuals with such disabilities unless they had a second person enter their votes for them, which is considered a compromise of the right to a secret ballot. Electronic voting systems offer extensive accessibility modes designed for voters who are vision impaired and/or have limited mobility, such as reading the ballot aloud and supporting a sip/puff or two-paddle input device. As I discuss in more length in another comment it is quite possible to meet these needs using a paper ballot system (by use of a ballot marking machine or BMM which may be integrated into the tabulator), but direct recording electronic (DRE) systems are less expensive to operate and in some cases purchase. So, unfortunately, many election authorities, forced by HAVA to replace their equipment on an extremely limited budget, opted for the cheapest option. These election authorities now cannot afford a complete replacement of their voting systems and so may be "locked in" to a DRE system by their vendor.

To improve US elections administration, it is imperative to address the severe funding limitations faced by most election authorities that may leave them little or no choice over the methods they use.