<div>Flexibility means that entrenched interests can be unseated by the system. For instance, a system that provides an excessive advantage to the well-established political parties - either de jure, as in closed party list systems, or de facto, as in the duopoly promoted by plurality - is inherently inflexible. Since future opportunities are, almost by definition, less well-represented than past glories, a more-flexible system is likely to have better utility by letting new opportunities flower.</div>
<div><br></div><div>Flexibility is also important for legitimacy. Anybody who is effectively frozen out of a system will - probably justly - see that system as corrupt. And, as with legitimacy, verifiability is key to flexibility.</div>
<div><br></div><div>But verifiability serves different purposes in the two cases. For legitimacy, it must avoid the appearance of fraud. But for flexibility, it must avoid the actual possibility of fraud. On the latter point, it's important to remember that opportunities for fraud go far beyond any verifiable ballot-counting process. For every Mexico 1988, where the ballot counting is corrupted, there are many cases of vote supression - the elimination of bogus "felons" in Florida 2000 of course springs to mind - or ballot stuffing is the problem. No voting system can prevent these issues; that is a larger struggle.</div>