Obviously, parties do not boycott elections, as Venezuela‘s largest opposition parties will do in Sunday’s National Assembly election, that they have any chance of winning. They boycott when they know they are going to lose, but when they calculate that they have a case to be made that the process itself is unfair.
Thus the point of a bocott is to provoke a crisis for the government. Any governing party bent on total domination of its opposition wants to keep an opposition involved right up until the time that it (i.e. the government) is secure enough to clamp down. When the opposition cries fraud and pulls out before it is at that point of domination, it is a crisis for the government. The facade of demcoracy has been torn down when you no longer can point to the persence of political competition as evidence that you aren’t authoritarian.
This is all done before an audience–both external and internal. The opposition is counting on this boycott exposing the ChÃ¡vez government as no longer democratic. The government will count on the opposition being seen as sore losers–in advance of any votes being cast and counted.
It is not unusual for boycotted elections to result in subsequent elections–sometimes well ahead of schedule–being called under different procedures negotiated between the government and opposition. The Peruvian experience of 2000-2001 comes to mind. But then there are also cases–some Eastern European cases after WWII–when the opposition is essentially never heard from again. I don’t see Venezuela–yet–in the latter category. The opposition is playing a very high stakes game. But given the increasing authoritarian bent of the ChÃ¡vez government, they had little choice but to shift the arena away from the elections themselves and into an arena in which the nature of the regime itself is at stake.
In other words, they are still competing. Just not, for now, for votes.