Inside the party we have good old RON to vote for (Re-Open Nominations) should we not agree with any candidate that steps forward.
Should we have this on the government ballot box as well?
I think there is a distinct difference between not voting, spoiling a vote and NOTA (None Of The Above)
On the night of GE2015's count, both mistakes and deliberately spoilt papers were lumped together. This makes it impossible to tell the difference between those who genuinely made an error and those who are actively rejecting the menu of politicians or protesting.
Non-voting can be mixed in with a variety of scenarios as well.
I believe a NOTA should be on the ballot.