No company or industry expropriated by the venezuelan government has been able to produce any profit because that is not in their plans.

You are totally right. The goal for them is to loot the companies and enrich themselves with stolen resources.

They need to keep people always in need of things that only the state can allegedly provide.

They have even said this. You can see it in this video

where Hector Rodriguez says they don't want poor people to become middle class because that could turn them into "escualidos", which as you surely know, is the disrespectful word that these totalitarians use when talking about people that don't support them.