Not always, Venezuelan oil requires high investment and gives low return (compared with other reserves), so it requires a competent government who can keep a level of education/safety and/or can let expertise flow in and set up infrastructure with an expectation that they will get a long term return. At this rate neither are going to happen and Venezuela is fucked unless China goes all in (I don’t think China is going to go all in).
This former minister explains that the reasons the military are backing Maduro are mainly financial, not political m.youtube.com/watch?v=UtcbV9HuHq8 Venezuela is essentially bankrupt and they can’t default on debt to China without getting into bigger problems or becoming fully dependent on the IMF/US.