I'd say that Chavez and his family doing more to enrich themselves than plan for the country's future when oil prices inevitably dropped played a large part.
You can say what you want. Doesn't change the fact that Chavez helped bring many of Venezuela's poor towards something approaching a dignified standard of living.
The economy was growing under Chavez's predecessors. Yes, it would have fared much, much better. What he did with oil is less important than what he did to the rest of the economy. Chavez was lucky, in a way, because he died right about the time math caught up with his economic policies.
Actually the economy suffered a massive contraction in the 80s when - surprise! - oil prices plunged. This is partly what led Chavez into power - mostly because while the country technically returned to growth - wages did not go up and unemployment did not go down.
Same cause last time as this time but last time was "all the fault of capitalism" and this one was "all the fault of socialism".
Capitalism is theft. It's mathematically impossible for the holder of capital to generate profit if he pays workers wages equal to the value their labor produces. Somebody has to be shortchanged somewhere along the line. The rich in Venezuela should be thankful they only have to deal with mild social democratic wealth redistribution policies.
Everything except capitalism is theft. In a free market every good exchange is voluntary - made because both parties have decided they're slightly better off with it (else, they wouldn't participate). Therefore, everything but a free market implies deals that are non-voluntary for at least one of the parties.
Voluntary economic associations are not theft. To say that capitalism is theft is to engage in sophistry. It's only theft if the workers are actually slaves.